534336

Appears in sequences

• Composite solutions to Sigma[x+d[x]] = Sigma[x]+d[x], where Sigma[] = A000203(), d[] = A000005().at n=7A063701
• The second crank moment function M_2(n).at n=32A220909
• a(n) = Sum_{0 < x,y,z,t <= n and gcd(x^2 + y^2 + z^2 + t^2, n)=1} gcd(x^2 + y^2 + z^2 + t^2 - 1, n).at n=22A239613