G.f.: [ Sum_{n>=0} (n+1)*(n+2)/2 * 4^(n^2) * x^n ]^(1/3).

A210310

G.f.: [ Sum_{n>=0} (n+1)*(n+2)/2 * 4^(n^2) * x^n ]^(1/3).

Terms

    a(0) =1a(1) =4a(2) =496a(3) =869824a(4) =21467623936

External references