i love this solution

מגניב ביותר!!!

lol FFS :P

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

Agreed. I see the same thing in C#. There are a lot of conversions in many of the solutions. However, as you pointed out there is a quite simple pure mathematical solution.

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.

Well bool is a sub-class of int so...