Empty radcoefficients list when initializing only first order terms #65

Hi everyone,

I'm wondering why no radcoefficients are initialized when only defining first order terms and how this can be justified through the mathematical expressions. My input for the functions section is

ALL: {
nradmax_by_orders: [5],
lmax_by_orders: [0]
}
or a different number unequal 0 instead of 5.
In the output potential the radcoefficients list/ array remains empty, like:
...
radparameters: [5.25]
radcoefficients: []
core-repulsion: [0, 0]
...

The way I understand the mathematical expressions in the appendix B section of the paper Efficient parametrization of the atomic cluster expansion there could be values for the coefficient. Or do I get there something wrong with the formulas?