Re: N = a^2 + b^2 + c^2 question

[hermann@stamm-wilbrandt.de]

On 2025-11-17 02:32, American Citizen wrote:
> In trying to obtain a fast but exhaustive algorithm for finding 3
> squares which sum to a given number n, I found that using n = 416666,
> I obtained 339 unique representations of [a,b,c] such that a^2+b^2+c^2
> = n.
>
> Can anyone verify that this count is correct for n?
If you generate all permutations, then all sign combinations and finally 
remove duplicates, you can check whether you get the correct number 
r_3(416666):
https://en.wikipedia.org/wiki/Sum_of_squares_function#k_=_3

You need to get 16248 entries:

? 12*qfbclassno(-4*416666)
16248
?


Regards,

Hermann.