Seems that the kata needs more tests. With this solution "ac" is equal to "bb"...

Yes, compared to other 7th kyu kata (which you can usually solve in under a minute) it feels more like a level 6 kata.

Nice. Using the Gauss formula schould be way faster than using range.

It is in conflict to PEP8 because it is too long. But I like it anyway. ;-)

It just looks fancy but may get a problem with maximum recursion depth pretty soon.

Beautiful, but too fragile. Exceeds maximum recursion depths pretty fast.

I like the name you chose for the list.

One of the tests should have checked type...;-)

Hmmmmm, a simple mathematical solution seems best but everyone is playing around with conversions in Python.

And I also think this should be level 7. It is a bit more complicated than the usual level 8 kata.

Lol, by far the best solution!

My solution (which I learned here on codewars from the solutions of a similar kata) is O((n).