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

A317663

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

Terms

    a(0) =1a(1) =3a(2) =54a(3) =1494a(4) =58248a(5) =2921346a(6) =179119836a(7) =12981530772

External references