a(n) = [x^n] Product_{k>=1} (1 + 3^n*x^k).

A318246

a(n) = [x^n] Product_{k>=1} (1 + 3^n*x^k).

Terms

    a(0) =1a(1) =3a(2) =9a(3) =756a(4) =6642a(5) =118341a(6) =388484100a(7) =10474704297a(8) =564988219686

External references