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

A380707

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

Terms

    a(0) =1a(1) =3a(2) =74a(3) =4578a(4) =520024a(5) =93638820a(6) =24469489008

External references