a(n) = [x^(n^2)] (Sum_{k=0..2*n} (k+1)*x^k)^n.

A322514

a(n) = [x^(n^2)] (Sum_{k=0..2*n} (k+1)*x^k)^n.

Terms

    a(0) =1a(1) =2a(2) =35a(3) =1624a(4) =169653a(5) =30961656a(6) =8792309747

External references