Re: number of ways of writing a nonnegative integer n as a sum of 3 squares (zero being allowed).

[hermann@stamm-wilbrandt.de]

On 2023-12-04 08:27, Markus Grassl wrote:
> It's not directly answering the question, but there is also the
> sequence https://oeis.org/A000164 which is described as
>
>   number of triples of integers [ i, j, k] such that i >= j >= k >= 0
> and n = i^2 + j^2 + k^2.
>
> Markus
Thank you for that oeis sequence.

I would be interested in slightly different number with i >= j >= k but 
k > 0.
Is that sequence known as well?

(for only two squares we know that #(n=j^2+k^2, j >= k > 0) = 2 for odd 
semiprimes)


Regards,

Hermann.