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User:Jianing Song
You don't try to extend these sequences: A000679, A094268, A257479.
Some really fast-growing functions in the OEIS: A056041/A266203 (the weak Goodstein function, growth ), A154714 (, growth ), A188545 (the "fuse" function, growth ), A028444/A060843 (the "BB" function, growth ).
- Note that , and (see here).
The most interesting sequences in my eyes: A046073, A105876, A298821.
The sequences I submitted myself that I'm most satisfied with: A306198, A400743.
Theta series for some best-known lattices
| Name | Description | Theta series | |
|---|---|---|---|
| Square | A004018 | A002654 | |
| Hexagonal, A2 | A004016 | A002324 | |
| Cubic | A005875 | - | |
| 4D cubic | A000118 | A046897 | |
| D4 | A004011 | A000593 |
Examples of factorizations
For a subgroup of , we write to be the fixed field of . We consider , with Galois group .
| Fixed field | Field | Discriminant | ||||
|---|---|---|---|---|---|---|
| 2304 | ||||||
| 576 | ||||||
| 2304 | ||||||
| 144 | ||||||
| 256 | ||||||
| 576 | ||||||
| 2304 |
Chebyshev's bias
| Subgroup | Coset | Primes | Coset | Primes | Coset | Primes |
|---|---|---|---|---|---|---|
| -1: A297354/A297355 | -1: A297356/A297357 0: A380877 |
very large | ||||
| very large | -1: A297447/A297448 0: A379989 differences: A379731 |
-1: A295353/A295354 | ||||
| -1: A398234 | -1: A398235 | -1: A398236 | ||||
The world of nuclides is full of mysteries
Unknown decays: 48Ca (β−), 123Te (β+), 149Sm (α), 180mTa (β+/β−/IT), 187Os (α), 222Fr (α), 247Cm (β−), 248Bk (α/β+/β−);
Unknown if decay is energetically possible: β− of 222Rn.
Bound-state decays
By conservation of energy, we have , where and are respectively the i-th ionization energy of element X and the next element.
Write be the total binding energies of electrons, then
.
In particular, for , we have ;
for , we have .
First category: for neutral atoms
Data from NIST (please beware that these are most predictions). All values are in unit of keV.
| Beta decay | ||||||
|---|---|---|---|---|---|---|
| 148Eu → 148Gd | -28 ± 10 | 11.6 | 59.06554 | 19 | 18.08746 | -22 |
| 163Dy → 163Ho | -2.831 ± 0.022 | 12.5 | 65.13713 | 49.806 | 19.84548 | 4.514 |
| 193Ir → 193Pt | -56.63 ± 0.30 | 15.9 | 90.65984 | 18.13 | 27.2647 | -45.27 |
| 194Au → 194Hg | -28 ± 4 | 16.8 | 95.89819 | 51 | 28.7966 | -16 |
| 202Tl → 202Pb | -40 ± 4 | 17.3 | 101.3367 | 44 | 30.3914 | -27 |
| 205Tl → 205Pb | -50.6 ± 0.5 | 17.3 | 101.3367 | 33.4 | 30.3914 | -37.5 |
| 213Po → 213At | -74 ± 5 | 18.4 | 109.8872 | 17 | 32.9085 | -59 |
| 215At → 215Rn | -88 ± 9 | 18.7 | 112.8422 | 6 | 33.7745 | -73 |
| 222Rn → 222Fr | -6 ± 8 | 19.2 | 115.8575 | 91 | 34.6741 | 9 |
| 244Pu → 244Am | -73.1 ± 2.7 | 22 | 142.1535 | 47.1 | 42.5273 | -52.6 |
| 243Am → 243Cm | -6.9 ± 1.6 | 24 | 145.7401 | 114.8 | 43.621 | 12.7 |
| 246Bk → 246Cf | -120 ± 60 | 23 | 153.124 | 10 | 45.845 | -100 |
Second category: for neutral atoms
Here we only consider the nuclides with . There are two cases:
There are excited states of the daughter with energies lying between and , thus providing more channels to decay when the parent is fully ionized: 187Re, 194Os, 227Ac, 241Pu, 247Cm, 250Cm, 249Bk.
There are no such excited states, so full ionizing only increases beta-decay energies of the original paths: 210Pb, 212At, 222Rn*, 228Ra.
| Beta decay | ||||||
|---|---|---|---|---|---|---|
| 187Re → 187Os* (9.756 keV) | -7.289 ± 0.002 | 15.2 | 85.61442 | 63.125 | 25.7921 | 3.303 |
See here, Table IV for details.
* It is not clear which category should 222Rn be put into.
Bound-state decays
Similarly, we have , hence
.
In particular, for , we have ;
for , we have .
| Double beta decay | ||||||
|---|---|---|---|---|---|---|
| 152Sm → 152Gd | -55.7 | 22.96 | 116.84945 | 38.2 | 75.85972 | -2.8 |
| 164Dy → 164Er | -25.0 | 25.2 | 133.08972 | 82.9 | 86.29105 | 36.1 |
| 214Po → 214Rn | -150 | 37.1 | 223.6886 | 37 | 144.6083 | -42 |
| 242Pu → 242Cm | -86.8 | 46 | 289.051 | 156.3 | 186.9038 | 54.1 |
Nuclides with the lowest mass among isobars of mass numbers 141 ~ 209
For 141 ≤ A ≤ 209, the nuclide with the lowest mass among isobars of A (141Pr, 142Nd, 143Nd, 144Nd, 145Nd, 146Sm, ..., 209Bi) are of particular interest. The following table lists their predicted half-lives here:
| A | Nuclide | log Tα (yr) |
|---|---|---|
| 146 | 146Sm | 7.96 |
| 147 | 147Sm | 11.03 |
| 186 | 186Os | 15.30 |
| 144 | 144Nd | 15.36 |
| 148 | 148Sm | 15.80 |
| 187 | 187Os | 17.66 |
| 149 | 149Sm | 18.47 |
| 151 | 151Eu | 18.66 |
| 209 | 209Bi | 19.30 |
| 176 | 176Hf | 20.51 |
| 177 | 177Hf | 22.00 |
| 145 | 145Nd | 22.93 |
| 192 | 192Pt | 22.96 |
| 178 | 178Hf | 23.64 |
| 185 | 185Re | 25.02 |
| 188 | 188Os | 26.28 |
| 150 | 150Sm | 28.05 |
| 191 | 191Ir | 29.09 |
| 170 | 170Yb | 29.24 |
| 189 | 189Os | 31.18 |
| 179 | 179Hf | 31.31 |
| 182 | 182W | 32.82 |
| 175 | 175Lu | 35.28 |
| 184 | 184W | 35.97 |
| 204 | 204Pb | 36.01 |
| 171 | 171Yb | 36.50 |
| 181 | 181Ta | 38.78 |
| 183 | 183W | 39.46 |
| 172 | 172Yb | 42.34 |
| 194 | 194Pt | 44.47 |
| 180 | 180Hf | 45.84 |
| 190 | 190Os | 47.39 |
| 169 | 169Tm | 47.63 |
| 198 | 198Hg | 52.15 |
| 154 | 154Gd | 52.60 |
| 173 | 173Yb | 62.37 |
| 195 | 195Pt | 64.13 |
| 166 | 166Er | 64.52 |
| 206 | 206Pb | 66.55 |
| 193 | 193Ir | 67.00 |
| 197 | 197Au | 71.78 |
| 174 | 174Yb | 75.31 |
| 203 | 203Tl | 80.57 |
| 167 | 167Er | 80.96 |
| 196 | 196Pt | 82.67 |
| 199 | 199Hg | 83.82 |
| 143 | 143Nd | 88.12 |
| 168 | 168Er | 91.90 |
| 200 | 200Hg | 95.46 |
| 153 | 153Eu | >100 |
| 160 | 160Dy | >100 |
| 152 | 152Sm | >100 |
| 155 | 155Gd | >100 |
| 156 | 156Gd | >100 |
| 208 | 208Pb | >100 |
| 161 | 161Dy | >100 |
| 157 | 157Gd | >100 |
| 207 | 207Pb | >100 |
| 159 | 159Tb | >100 |
| 158 | 158Gd | >100 |
| 165 | 165Ho | >100 |
| 162 | 162Dy | >100 |
| 201 | 201Hg | >100 |
| 163 | 163Dy | >100 |
| 142 | 142Nd | >100 |
| 202 | 202Hg | >100 |
| 164 | 164Er | >100 |
| 205 | 205Tl | >100 |
| 141 | 141Pr | >100 |
For nuclides in the table with predicted alpha half-lives longer than 10100 years (including being stable to alpha decay), cluster decay modes (for example 16O emission) must be taken into account when modeling the half-lives. It seems that there is no concensus on predicting cluster decay half-lives, in contrast to alpha decay.
Warning: The following table is purely insane and contains nothing serious.
| Nuclide | log Tα (yr) | log T12C (yr) | log T14C (yr) | log T18O (yr) | log T24Ne (yr) | minimum |
|---|---|---|---|---|---|---|
| 141Pr | - | 245.75 | - | 210.85 | 291.50 | 210.85 |
| 205Tl | 283.07 | 201.02 | 201.97 | 219.02 | 226.19 | 201.02 |
| 164Dy | - | 204.89 | 210.06 | 206.46 | 187.41 | 187.41 |
| 202Hg | 305.64 | 188.90 | 186.02 | 204.49 | 215.28 | 186.02 |
| 142Nd | - | 188.35 | 498.81 | 185.32 | 253.31 | 185.32 |
| 163Dy | - | 193.71 | 202.49 | 190.41 | 181.18 | 181.18 |
| 201Hg | 171.10 | 174.61 | 173.33 | 190.21 | 210.54 | 171.10 |
| 162Dy | 336.47 | 171.38 | 175.29 | 171.00 | 173.99 | 171.00 |
| 165Ho | 242.65 | 169.21 | 194.22 | 188.44 | 187.58 | 169.21 |
| 158Gd | - | 175.63 | 159.36 | 166.90 | 178.65 | 159.36 |
| 159Tb | - | 159.93 | 157.32 | 157.48 | 179.61 | 157.32 |
| 207Pb | 157.17 | 193.02 | 198.06 | 215.52 | 230.38 | 157.17 |
| 157Gd | - | 150.39 | 144.38 | 152.04 | 181.80 | 144.38 |
| 161Dy | 132.24 | 156.10 | 160.63 | 157.78 | 175.85 | 132.24 |
| 208Pb | 128.87 | 203.20 | 202.37 | 223.74 | 236.49 | 128.87 |
| 156Gd | - | 127.89 | 130.31 | 139.36 | 182.19 | 127.89 |
| 155Gd | 304.37 | 111.31 | 117.55 | 127.23 | 184.32 | 111.31 |
| 152Sm | 164.24 | 115.84 | 111.23 | 127.65 | 187.96 | 111.23 |
| 160Dy | 110.29 | 135.61 | 144.68 | 145.50 | 177.93 | 110.29 |
| 153Eu | 144.69 | 108.55 | 110.99 | 122.63 | 186.92 | 108.55 |
I wish 4He had energy 6 MeV higher
Then α decays would essentially disappear. Warning: The following table is purely insane and contains nothing serious.
| Nuclide | Q8Be (MeV) | log T8Be (yr) | Q12C (MeV) | log T12C (yr) | Q14C (MeV) | log T14C (yr) | minimum |
|---|---|---|---|---|---|---|---|
| 215At | 14.84 | 12.03 | 21.89 | 26.09 | 22.13 | 25.62 | 12.03 |
| 212Rn | 11.51 | 19.88 | 20.84 | 28.16 | 19.28 | 31.22 | 19.88 |
| 214Rn | 14.52 | 12.78 | 23.03 | 23.85 | 22.16 | 25.56 | 12.78 |
| 216Rn | 17.06 | 6.79 | 24.94 | 20.10 | 24.58 | 20.81 | 6.79 |
| 217Rn | 16.33 | 8.51 | 25.95 | 18.11 | 25.91 | 18.19 | 8.51 |
| 218Rn | 15.00 | 11.65 | 26.16 | 17.70 | 26.89 | 16.27 | 11.65 |
| 220Rn | 13.22 | 15.85 | 23.71 | 22.52 | 28.54 | 13.02 | 13.02 |
| 222Rn | 11.61 | 19.64 | 21.49 | 26.88 | 26.45 | 17.13 | 17.13 |
| 219Fr | 15.53 | 10.40 | 29.65 | 10.84 | 29.42 | 11.29 | 10.40 |
| 218Ra | 17.66 | 5.38 | 30.43 | 9.31 | 28.74 | 12.63 | 5.38 |
| 220Ra | 15.70 | 10.00 | 32.02 | 6.18 | 31.04 | 8.11 | 6.18 |
| 221Ra | 14.68 | 12.40 | 30.58 | 9.01 | 32.40 | 5.44 | 5.44 |
| 222Ra | 13.85 | 14.36 | 29.05 | 12.02 | 33.05 | 4.16 | 4.16 |
| 223Ra | 12.83 | 16.77 | 27.72 | 14.63 | 31.83 | 6.56 | 6.56 |
| 224Ra | 12.10 | 18.49 | 26.37 | 17.29 | 30.53 | 9.11 | 9.11 |
| 226Ra | 10.37 | 22.57 | 23.85 | 22.24 | 28.20 | 13.69 | 13.69 |
| 225Ac | 12.30 | 18.02 | 26.87 | 16.30 | 30.48 | 9.21 | 9.21 |
| 224Th | 14.80 | 12.12 | 30.36 | 9.45 | 32.93 | 4.39 | 4.39 |
| 226Th | 13.04 | 16.27 | 27.67 | 14.73 | 30.55 | 9.07 | 9.07 |
| 228Th | 11.22 | 20.56 | 24.99 | 20.00 | 28.20 | 13.65 | 13.65 |
The primary decay mode of 226Th without α decay would perhaps be 18O emission (unknown in the real world).
The primary decay mode of 228Th without α decay would be 20O emission (known in the real world; the partial half-life is 1.69×1013 years).
The primary decay mode of 230U without α decay would be 22Ne emission (known in the real world; the partial half-life is 1.15×1012 years).
The primary decay mode of 232U without α decay would be 24Ne emission (known in the real world; the partial half-life is 7.74×1012 years).
Hands in Poker
Imagine that an online system of Poker allows players to customize the number of suits d and the number of ranks n. What should be the ranking of hands in the game?
By the way, a straight means five cards with consecutive ranks. However, the highest-ranking card can be used as high or low in a straight, and thus there are of them in terms of card values.
For the standard deck, the card ranking is 2 3 4 5 6 7 8 9 10 J Q K A, hence the lowest-ranking straight is A2345;
In Six-plus hold 'em, the card ranking is 6 7 8 9 10 J Q K A, hence the lowest-ranking straight is A6789;
In the deck of Five Crowns, the card ranking is 3 4 5 6 7 8 9 10 J Q K, hence the lowest-ranking straight is K3456.
When we pick randomly 5 cards from a deck with general and , the number of combinations of each hand is given as follows. A hand having a smaller number of combinations in the table ranks higher, except that a pair always beats high card (even if high card occurs less often if
The concrete mode of game (Texas, Omaha, or anything original) is irrelevant to the determination of ranking of hands.
| Hand | Card value type | Suit combinations of hand | Card value combinations of hand |
|---|---|---|---|
| Straight flush | 1+1+1+1+1 | ||
| Five of a kind | 5 | ||
| Four of a kind | 4+1 | ||
| Full house | 3+2 | ||
| Flush | 1+1+1+1+1 | ||
| Straight | 1+1+1+1+1 | ||
| Three of a kind | 3+1+1 | ||
| Two pairs | 2+2+1 | ||
| One pair | 2+1+1+1 | ||
| High card | 1+1+1+1+1 | ||
| Total (= suit combinations card value combinations) | |||
Please note that we cannot add a hand that "contains one card in each suit" for because, as , 100% of draws of 5 cards consist of 5 cards in different suits. This is a special case of a principle when setting the list of hands: a hand is only valuable when it contains "similarities", not "differences".
Other observations should be mentioned. We always have
Straight flush > Four of a kind > Full house > Straight > Three of a kind > Two pairs > One pair > High card for ;
Five of a kind > Straight flush > Four of a kind > Full house > Straight > Three of a kind > Two pairs > One pair > High card for ; and
Straight flush > Five of a kind > Four of a kind > Full house > Straight > Three of a kind > Two pairs > One pair > High card for ,
but the positions of a flush and a straight depend on the specific value of . A flush can rank anywhere between a straight flush and high card, while a straight can only rank below a five-of-a-kind and above a three-of-a-kind. The turning point of the positions of
a flush and a full house is as ;
a flush and a straight is as ;
evidently enough, a five-of-a-kind ranks lower than a flush if and higher if (hence the turning point is ).
Turning points for specific :
: a flush and a full house change positions at , and a flush and a straight change positions at ;
: a flush and a four-of-a-kind change positions at , and a flush and a full house change positions at ;
: a flush and a four-of-a-kind change positions at .
Notice. Somebody may think that the ranking of hands should be determined by 7-card combinations rather than 5-card combinations, since Poker is a game of seeing 7 cards. The problem is, a 7-card combination contains in general 5-card combinations in different categories, so how to assess the value of each 7-card combination? In other words, the number of 7-card combinations of each hand can only be calculated after the determination of the ranking, not before. Since combinations of higher rankings need to be deducted while determining the number of each 7-card combination, those numbers no longer reflect the probability of getting each hand.
Standard deck (, )
| Hand | Combinations |
|---|---|
| Straight flush | 40 |
| Four of a kind | 624 |
| Full house | 3744 |
| Flush | 5108 |
| Straight | 10200 |
| Three of a kind | 54912 |
| Two pairs | 123552 |
| One pair | 1098240 |
| High card | 1302540 |
| Total | 2598960 |
Six-plus hold 'em (, )
In the game Six-plus hold 'em, there are only 9 card values used: 6 7 8 9 10 J Q K A from the lowest to the highest.
| Hand | Combinations |
|---|---|
| Straight flush | 24 |
| Four of a kind | 288 |
| Flush | 480 |
| Full house | 1728 |
| Straight | 6120 |
| Three of a kind | 16128 |
| Two pairs | 36288 |
| One pair | 193536 |
| High card | 122400 |
| Total | 376992 |
Deck of French Tarot (, )
The only commercially available deck of playing cards with more than 13 cards in each suit. It is difficult for people from other countries to imagine just how much the French enjoy playing tarot.
| Hand | Combinations |
|---|---|
| Straight flush | 44 |
| Four of a kind | 728 |
| Full house | 4368 |
| Flush | 7964 |
| Straight | 11220 |
| Three of a kind | 69888 |
| Two pairs | 157248 |
| One pair | 1537536 |
| High card | 2030820 |
| Total | 3819816 |
Deck of Uno No Mercy (, )
In a deck of Uno No Mercy each color contains 16 kinds of different cards: 0-9, Reverse, Skip, Draw 2, Draw 4, Skip Everyone, Discard All. I list this pair of here because is the least value such that a straight beats a flush.
| Hand | Combinations |
|---|---|
| Straight flush | 52 |
| Four of a kind | 960 |
| Full house | 5760 |
| Straight | 13260 |
| Flush | 17420 |
| Three of a kind | 107520 |
| Two pairs | 241920 |
| One pair | 2795520 |
| High card | 4442100 |
| Total | 7624512 |
Deck of Five Crowns (, )
The only commercially available deck of playing cards with more than 4 suits. A quite niche board game.
| Hand | Combinations |
|---|---|
| Five of a kind | 11 |
| Straight flush | 40 |
| Flush | 2270 |
| Four of a kind | 2750 |
| Full house | 11000 |
| Straight | 24960 |
| Three of a kind | 123750 |
| Two pairs | 247500 |
| One pair | 1650000 |
| High card | 1416480 |
| Total | 3478761 |
Non-uniqueness of the par contract in contract bridge
Have you noticed that in rare cases, when some suit is fixed to be the trump suit, the number of tricks for N/S (the number of tricks which can be taken by NS if either N or S is the declarer) and the number of tricks for E/W can add up to more than 13? If so, the par contract may depend on who bids first! (See here for examples!)
First let's think about the question of finding the par contract in general. Here, instead of comparing contracts that either side can make, we compare the double dummy result. I will write, say, "we have the condition C=9", to mean if club is the trump suit, then the double dummy result is that when either I and my partner is the declarer, the optimal result for us is exactly 9 tricks.
Let A be the highest-ranking condition (in the sequence C=7, D=7, H=7, S=7, NT=7, ..., C=13, D=13, H=13, S=13, NT=13) that we have, and B be the highest-ranking condition that the opponents have. Suppose WLOG that A ranks higher than or equal to B. Now we list all the conditions we have that rank at least as high as B, then left over the most valuable ones. The least to the most valuable conditions are as follows:
| C=7, D=7 |
| H=7, S=7 |
| NT=7, C=8, D=8 |
| H=8, S=8, C=9, D=9 |
| NT=8 |
| C=10, D=10 |
| H=9, S=9 |
| NT=9, C=11, D=11 |
| H=10, S=10 |
| NT=10 |
| H=11, S=11 |
| NT=11 |
| C=12, D=12 |
| H=12, S=12 |
| NT=12 |
| C=13, D=13 |
| H=13, S=13 |
| NT=13 |
The resulting conditions reflect the ideal contract in the bidding process if sacrifice bids are not used. I call these conditions the optimal conditions of a deal.
Now we check the double dummy result of our opponents in the suits of the optimal conditions. Pick the highest-ranking (in the sequence C=0, D=0, H=0, S=0, NT=0, ..., C=13, D=13, H=13, S=13, NT=13) condition (call it B'). If B'+1 ranks higher than B (if B' is, say, C=7, then B'+1 is the condition C=8), then the suit of B' is the key suit. If the number of tricks for N/S and the number of tricks for E/W add up to more than 13 given that the key suit is the trump suit, then it is very likely that the par contract depends on which side bids first!
See these very long tables made by me for more details.
Table of minimal polynomial of -2 cos(2π/n) (note the minus sign!)
Let Pn be the minimal polynomial of for n ≥ 3, and P1 = P2 := 1. Then we have:
for even n; for odd n.
PARI code:
Prod(n) = my(M = [X,-1;1,0]); if(n%2==0, (M^(n/2))[2,1], (M^((n-1)/2) * [1;1])[1,1]) P(n) = my(P = 1); fordiv(n, d, P *= Prod(n/d)^moebius(d)); P
| n | Pn | Pn(k) for k = 3 | k = 4 | k = 6 |
|---|---|---|---|---|
| 3 | 2 | 3 | 5 | |
| 4 | 3 | 4 | 6 | |
| 5 | 5 | 11 | 29 | |
| 6 | 4 | 5 | 7 | |
| 7 | 13 | 41 | 169 | |
| 8 | 7 | 14 | 34 | |
| 9 | 17 | 51 | 197 | |
| 10 | 11 | 19 | 41 | |
| 11 | 89 | 571 | 5741 | |
| 12 | 6 | 13 | 33 | |
| 13 | 233 | 2131 | 33461 | |
| 14 | 29 | 71 | 239 | |
| 15 | 61 | 241 | 1345 | |
| 16 | 47 | 194 | 1154 | |
| 17 | 1597 | 29681 | 1136689 | |
| 18 | 19 | 53 | 199 | |
| 19 | 4181 | 110771 | 6625109 | |
| 20 | 41 | 181 | 1121 |
Let p be an odd prime not dividing k2 - 4, then there exists a unique number of the form such that p divides Pα(k,p)(k). The parity of m is determined by the value of . Consider the case k = 4, so k2 - 4 = 12 and -(k - 2) = -2:
| p | 5 | 7 | 11 | 13 | 17 | 19 | 23 | 29 | 31 | 37 | 41 | 43 | 47 | 53 | 59 | 61 | 67 | 71 | 73 | 79 | 83 | 89 | 97 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| corresponding m | 1 | 1 | 2 | 1 | 2 | 2 | 1 | 1 | 1 | 1 | 6 | 2 | 1 | 3 | 2 | 1 | 4 | 5 | 2 | 1 | 2 | 2 | 6 |
| -1 | -1 | 1 | -1 | 1 | 1 | -1 | -1 | -1 | -1 | 1 | 1 | -1 | -1 | 1 | -1 | 1 | -1 | 1 | -1 | 1 | 1 | 1 |
(Also, you may find this document written by myself interesting. At the end of page 4, there is a conjecture on the densities of the occurrences of α(k,p) odd, α(k,p) ≡ 2 (mod 4), and 4 | α(k,p)).
Wall-Sun-Sun primes in Lucas sequences
Let T(P,Q,n) be the n-th term of the Lucas sequence (P,Q) of the first kind, then we have for k ≥ 3. For odd primes p that are not factors of k2 - 4 (so that is even), we always have , so it would be meaningful to ask when p2 divides this quantity. The n-Wall-Sun-Sun primes correspond to k = n2 + 2.
Note the product formula for even n and for odd n, where Pn is the minimal polynomial of .
The OEIS has A238490 for k = 4, A238736 for k = 6 and A337791 for k = 38.
Numbering of flags in Endless mode of Plants vs. Zombies
Let (a 32-bit signed integer) be the number of the current level. Set (32-bit signed multiplication), then:
The level starts at flag (32-bit signed integer division) and ends at flag . This will be written as flags in the table at the end.
For , the -th flag of level has zombies if and only if (32-bit signed addition) or . Only Flag Zombies appear for waves not in these ranges.
For Pool and Fog settings, the game crashes on a level when there are no zombies other than Flag Zombies in the 20 waves.
Let's look at for an example. We have , so we start at flag and end at flag . Notice: The next level crashes with Pool or Fog because there would be no zombies. That's why many believe that the game only has 107374184 flags, which is of course not true (just try Day, Night, or Roof).
| Wave | 1 | 2 | 3 | 4 | 5 | ... | 20 |
|---|---|---|---|---|---|---|---|
| 1073741821 | 1073741822 | 1073741823 | 1073741824 | 1073741825 | ... | 1073741840 | |
| Has zombies? | Yes | Yes | Yes | Yes | No | ... | No |
Look at also . Then , so we start at flag and end at flag . Warning: The next level starts at flag as we plug in .
| Wave | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | ... | 20 |
|---|---|---|---|---|---|---|---|---|---|---|
| 2147483641 | 2147483642 | 2147483643 | 2147483644 | 2147483645 | 2147483646 | 2147483647 | -2147483648 | ... | -2147483636 | |
| Has zombies? | No | No | No | No | No | No | Yes | Yes | ... | Yes |
A summarizing table:
These waves are normal (-1~1073741824)
These waves have only Flag Zombies (game crash with Pool or Fog) (1073741825~2147483646, -1073741823~-2)
These waves are somehow normal (2147483647~-1073741824)
| Period | Quarter-period | Levels | # of levels | Flags contained | Wave numbers |
|---|---|---|---|---|---|
| 1 | 1a | 0~53687091 | 53687092 | [0,107374184) | Levels 0~53687090 (flags [0,107374182)): 1~1073741820 Level 53687091 (flags [107374182,107374184)): 1073741821~1073741824, 1073741825~1073741840 |
| 1b | 53687092~107374182 | 53687091 | [107374184,214748366) | Levels 53687092~107374181 (flags [107374184,214748364)): 1073741841~2147483640 Level 107374182 (flags [214748364,214748366)): 2147483641~2147483646, 2147483647~-2147463636 | |
| 1c | 107374183~161061273 | 53687091 | [-214748363,-107374181) | Levels 107374183~161061272 (flags [-214748363,-107374183)): -2147483635~-1073741836 Level 161061273 (flags [-107374183,-107374181)): -1073741835~-1073741824, -1073741823~-1073741816 | |
| 1d | 161061274~214748364 | 53687091 | [-107374181,1) | Levels 161061274~214748363 (flags [-107374181,-1)): -1073741815~-16 Level 214748364 (flags [-1,1)): -15~-2, -1~4 | |
| 2 | 2a | 214748365~268435455 | 53687091 | [0,107374182) | Levels 214748365~268435455 (flags [0,107374182)): 5~1073741824 |
| 2b | 268435456~322122547 | 53687092 | [107374182,214748366) | Levels 268435456~322122546 (flags [107374182,214748364)): 1073741825~2147483644 Level 322122547 (flags [214748364,214748366)): 2147483645~2147483646, 2147483647~-2147483632 | |
| 2c | 322122548~375809638 | 53687091 | [-214748363,-107374181) | Levels 322122548~375809637 (flags [-214748363,-107374183)): -2147483631~-1073741832 Level 375809638 (flags [-107374183,-107374181)): -1073741831~-1073741824, -1073741823~-1073741812 | |
| 2d | 375809639~429496729 | 53687091 | [-107374181,1) | Levels 375809639~429496728 (flags [-107374181,-1)): -1073741811~-12 Level 429496729 (flags [-1,1)): -11~-2, -1~8 | |
| 3 | 3a | 429496730~483183820 | 53687091 | [0,107374182) | Levels 429496730~483183819 (flags [0,107374180)): 9~1073741808 Level 483183820 (flags [107374180,107374182)): 1073741809~1073741824, 1073741825~1073741828 |
| 3b | 483183821~536870911 | 53687091 | [107374182,214748364) | Levels 483183821~536870910 (flags [107374182,214748362)): 1073741829~2147383628 Level 536870911 (flags [214748362,214748364)): 2147483629~2147483646, 2147483647~-2147483648 | |
| 3c | 536870912~590558003 | 53687092 | [-214748364,-107374180) | Levels 536870912~590558002 (flags [-214748364,-107374182)): -2147483647~-1073741828 Level 590558003 (flags [-107374182,-107374180)): -1073741827~-1073741824, -1073741823~-1073741808 | |
| 3d | 590558004~644245094 | 53687091 | [-107374180,2) | Levels 590558004~644245093 (flags [-107374180,0)): -1073741807~-8 Level 644245094 (flags [0,2)): -7~-2, -1~12 | |
| 4 | 4a | 644245095~697932185 | 53687091 | [1,107374183) | Levels 644245095~697932184 (flags [1,107374181)): 13~1073741812 Level 697932185 (flags [107374181,107374183)): 1073741813~1073741824, 1073741825~1073741832 |
| 4b | 697932186~751619276 | 53687091 | [107374183,214748365) | Levels 697932186~751619275 (flags [107374183,214748363)): 1073741833~2147483632 Level 751619276 (flags [214748363,214748365)): 2147483633~2147483646, 2147483647~-2147483644 | |
| 4c | 751619277~805306367 | 53687091 | [-214748364,-107374182) | Levels 751619277~805306367 (flags [-214748364,-107374182)): -2147483643~-1073741824 | |
| 4d | 805306368~858993459 | 53687092 | [-107374182,2) | Levels 805306368~858993458 (flags [-107374182,0)): -1073741823~-4 Level 858993459 (flags [0,2)): -3~-2, -1~16 | |
| 5 | 5a | 858993460~912680550 | 53687091 | [1,107374183) | Levels 858993460~912680549 (flags [1,107374181)): 17~1073741816 Level 912680550 (flags [107374181,107374183)): 1073741816~1073741824, 1073741825~1073741836 |
| 5b | 912680551~966367641 | 53687091 | [107374183,214748365) | Levels 912680551~966367640 (flags [107374183,214748363)): 1073741837~2147483636 Level 966367641 (flags [214748363,214748365)): 2147483637~2147483646, 2147483647~-2147483640 | |
| 5c | 966367642~1020054732 | 53687091 | [-214748364,-107374182) | Levels 966367642~1020054731 (flags [-214748364,-107374184)): -2147483639~-1073741840 Level 1020054732 (flags [-107374184,-107374182)): -1073741839~-1073741824, -1073741823~-1073741820 | |
| 5d | 1020054733~1073741823 | 53687091 | [-107374182,0) | Levels 1020054733~1073741822 (flags [-107374182,-2)): -1073741819~-20 Level 1073741823 (flags [-2,0)): -19~-2, -1~0 |
List of telephone number ranges
I: 134Ba 135Ba 136Ba 137Ba 138Ba 139La 147Sm 150Sm 151Eu 152Sm 157Gd 158Gd 159Tb 172Yb 178Hf 182W 183W 184W 187Os 188Os 195Pt 197Au 198Hg
II: 130Xe 131Xe 132Xe 155Gd 156Gd 166Er 175Lu 176Hf 185Re 186Os 196Pt
III: 133Cs 153Eu 173Yb 177Hf 180Hf 181Ta 189Os 190Os 191Ir 193Ir 199Hg
IV: 192Pt
Virtual: 162Dy 165Ho 167Er 170Yb 171Yb
Factoring rational primes on the quadratic number field with discriminant
- D = -376. Decomposing: A191056; remaining inert: A191086.
- D = -344. Decomposing: A191051; remaining inert: A191083.
- D = -312. Decomposing: A191047; remaining inert: A191080.
- D = -280. Decomposing: A191043; remaining inert: A191078.
- D = -248. Decomposing: A191040; remaining inert: A191076.
- D = -184. Decomposing: A191032; remaining inert: A191071.
- D = -163. Decomposing: A296921; remaining inert: A296915; not remaining inert: A257362.
- D = -152. Decomposing: A191028; remaining inert: A191069.
- D = -120. Decomposing: A191023; remaining inert: A191066.
- D = -95. Decomposing: A191057; remaining inert: A191087.
- D = -91. Decomposing: A191054; remaining inert: A191085.
- D = -88. Decomposing: A191020; remaining inert: A191064.
- D = -87. Decomposing: A191052; remaining inert: A191084.
- D = -83. Decomposing: A191050; remaining inert: A191082.
- D = -79. Decomposing: A191048; remaining inert: A191081.
- D = -71. Decomposing: A191044; remaining inert: A191079.
- D = -68. Decomposing: A296929; remaining inert: A296930; not remaining inert: A296931.
- D = -67. Decomposing: A191041; remaining inert: A191077; not remaining inert: A106933.
- D = -59. Decomposing: A191038; remaining inert: A191075.
- D = -56. Decomposing: A191017; remaining inert: A191061; not decomposing: A274504.
- D = -55. Decomposing: A191036; remaining inert: A191074.
- D = -52. Decomposing: A296926; remaining inert: A296927; not remaining inert: A296928 U {2}.
- D = -51. Decomposing: A191034; remaining inert: A191073.
- D = -47. Decomposing: A191033; remaining inert: A191072.
- D = -43. Decomposing: A191031; remaining inert: A184902; not remaining inert: A106891.
- D = -40. Decomposing: A155488; remaining inert: A296925; not remaining inert: A293859.
- D = -39. Decomposing: A191029; remaining inert: A191070.
- D = -35. Decomposing: A191026; remaining inert: A191068.
- D = -31. Decomposing: A191024; remaining inert: A191067.
- D = -24. Decomposing: A157437; remaining inert: A191059; not remaining inert: A296924.
- D = -23. Decomposing: A191021; remaining inert: A191065; not remaining inert: A296932.
- D = -20. Decomposing: A139513; remaining inert: A003626; not remaining inert: A240920 = A296922 U {2}; not decomposing: A296923 U {5}.
- D = -19. Decomposing: A191019; remaining inert: A191063; not remaining inert: A106863.
- D = -15. Decomposing: A191018; remaining inert: A191062.
- D = -11. Decomposing: A296920; remaining inert: A191060; not remaining inert: A056874.
- D = -8. Decomposing: A033200; remaining inert: A003628; not remaining inert: A033203; not decomposing: A045355.
- D = -7. Decomposing: A045386; remaining inert: A003625; not remaining inert: A045373; not decomposing: A045399.
- D = -4. Decomposing: A002144; remaining inert: A002145; not remaining inert: A002313; not decomposing: A045326.
- D = -3. Decomposing: A002476; remaining inert: A003627 = A007528 U {2}; not remaining inert: A007645; not decomposing: A045309 = A045410 U {2}.
- D = 5. Decomposing: A045468 = A064739 \ {2}; remaining inert: A003631 = A097957 U {2}; not remaining inert: A038872; not decomposing: A042993.
- D = 8. Decomposing: A001132 = A097958 \ {3}; remaining inert: A003629; not remaining inert: A038873; not decomposing: A042999.
- D = 12. Decomposing: A097933; remaining inert: A003630; not remaining inert: A038874 = A296933 U {2}; not decomposing: A038875 U {3}.
- D = 13. Decomposing: A296937; remaining inert: A038884; not remaining inert: A038883; not decomposing: A120330.
- D = 17. Decomposing: A296938; remaining inert: A038890; not remaining inert: A038889.
- D = 21. Remaining inert: A038894; not remaining inert: A038893.
- D = 24. Decomposing: A097934; remaining inert: A038877; not remaining inert: A038876.
- D = 28. Decomposing: A296934; remaining inert: A003632; not remaining inert: A038878.
- D = 29. Decomposing: A191022; remaining inert: A038902; not remaining inert: A038901.
- D = 33. Remaining inert: A038908; not remaining inert: A038907.
- D = 37. Decomposing: A191027; remaining inert: A038914; not remaining inert: A038913.
- D = 40. Decomposing: A097955; remaining inert: A038880; not remaining inert: A038879.
- D = 41. Decomposing: A191030; remaining inert: A038920; not remaining inert: A038919.
- D = 44. Decomposing: A296935; remaining inert: A296936; not remaining inert: A038881 U {2}; not decomposing: A038882 U {11}.
- D = 53. Decomposing: A191035; remaining inert: A038932; not remaining inert: A038931.
- D = 56. Remaining inert: A038886; not remaining inert: A038885.
- D = 57. Remaining inert: A038936; not remaining inert: A038935.
- D = 60. Decomposing: A097956; remaining inert: A038888; not remaining inert: A038887.
- D = 61. Decomposing: A191039; remaining inert: A038942; not remaining inert: A038941.
- D = 65. Remaining inert: A038946; not remaining inert: A038945.
- D = 69. Decomposing: A191042; remaining inert: A038952; not remaining inert: A038951.
- D = 73. Decomposing: A191045; remaining inert: A038958; not remaining inert: A038957.
- D = 76. Decomposing: A297175; remaining inert: A297176 = A038892 \ {2}; not remaining inert: A038891 U {2}.
- D = 77. Remaining inert: A038962; not remaining inert: A038961.
- D = 85. Remaining inert: A038972; not remaining inert: A038971.
- D = 88. Remaining inert: A038896; not remaining inert: A038895.
- D = 89. Decomposing: A191053; remaining inert: A038978; not remaining inert: A038977.
- D = 92. Decomposing: A297177; remaining inert: A038898; not remaining inert: A038897.
- D = 93. Decomposing: A191055; remaining inert: A038982; not remaining inert: A038981.
- D = 97. Decomposing: A191058; remaining inert: A038988; not remaining inert: A038987.
- D = 104. Remaining inert: A038900; not remaining inert: A038899.
- D = 120. Decomposing: A097959; remaining inert: A038904; not remaining inert: A038903.
- D = 124. Remaining inert: A038906; not remaining inert: A038905.
- D = 136. Decomposing: A191025; remaining inert: A038910; not remaining inert: A038909.
- D = 140. Remaining inert: A038912 \ {2}; not remaining inert: A038911 U {2}.
- D = 152. Remaining inert: A038916; not remaining inert: A038915.
- D = 156. Remaining inert: A038918; not remaining inert: A038917.
- D = 168. Remaining inert: A038922; not remaining inert: A038921.
- D = 172. Remaining inert: A038924 \ {2}; not remaining inert: A038923 U {2}.
- D = 184. Remaining inert: A038926; not remaining inert: A038925.
- D = 188. Remaining inert: A038928; not remaining inert: A038927.
- D = 204. Remaining inert: A038930 \ {2}; not remaining inert: A038929 U {2}.
- D = 220. Remaining inert: A038934; not remaining inert: A038933.
- D = 232. Decomposing: A191037; remaining inert: A038938; not remaining inert: A038937.
- D = 236. Remaining inert: A038940 \ {2}; not remaining inert: A038939 U {2}.
- D = 248. Remaining inert: A038944; not remaining inert: A038943.
- D = 264. Remaining inert: A038948; not remaining inert: A038947.
- D = 268. Remaining inert: A038950 \ {2}; not remaining inert: A038949 U {2}.
- D = 280. Remaining inert: A038954; not remaining inert: A038953.
- D = 284. Remaining inert: A038956; not remaining inert: A038955.
- D = 296. Decomposing: A191046; remaining inert: A038960; not remaining inert: A038959.
- D = 312. Remaining inert: A038964; not remaining inert: A038963.
- D = 316. Remaining inert: A038966; not remaining inert: A038965.
- D = 328. Decomposing: A191049; remaining inert: A038968; not remaining inert: A038967.
- D = 332. Remaining inert: A038970 \ {2}; not remaining inert: A038969 U {2}.
- D = 344. Remaining inert: A038974; not remaining inert: A038973.
- D = 348. Remaining inert: A038976; not remaining inert: A038975 U {2}.
- D = 364. Remaining inert: A038980 \ {2}; not remaining inert: A038979 U {2}.
- D = 376. Remaining inert: A038984; not remaining inert: A038983.
- D = 380. Remaining inert: A038986; not remaining inert: A038985.