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

A319466

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

Terms

    a(0) =1a(1) =2a(2) =15a(3) =201a(4) =3807a(5) =93103a(6) =2788528a(7) =98816388a(8) =4043274742a(9) =187583369889

External references