It's not really about finding a formula, but an algorithm to compute the value in less time. The final solution involves quite a bit of both coding and maths.

I, as an amateur coder, found a lot of fun playing with pentomino problems..

So I just wanted to share!!

Thanks

I updated the Go translation myself.

The author does not have to be active for a translation to get accepted.

See my reply above. Please create a new fork of your translation with all updates. I will check it and approve it.

b may be as high as 10**18 in Big numbers tests. The reference solution should be updated: replace math.Pow with repeated multiplication. You may also increase the number of tests but I don't think it is necessary.

Go random tests expect incorrect results for large numbers. Do not use math.Pow in the solution (float64 cannot be used for integers larger than $2^{53}$).

An example:

n = 9010954778750400
m = 9010954778750410
Expected
    <[]int | len:1, cap:1>: [9010954778750401]
to equal
    <[]int | len:1, cap:1>: [9010954778750400]

I added it.

Approved

Yes, I do.

i think, this line - "for num, color in zip(range(number, number+3), (2, 1, 1)):"
should be like this - "for num, color in zip(range(number, number+3), (2, 1, 0)):"

I don't do Go at all, so I can't be of any technical help, sorry.

Ok, I found the reason: the random tests still pass because they don't just compare the output string against another (because several solutions may be possible), so the leading and trailing new lines, which are just about formatting, don't cause problems. The fixed tests, on the other hand, fail because the strings are different.