102237domain: NAppears in sequencesLet p = n-th prime == 3 mod 8; a(n) = sum of quadratic residues mod p.at n=31A282723a(n) = Sum_{k=0..n-1} binomial(4*k-1,k) * binomial(4*n-4*k,n-k-1).at n=6A386565