E.g.f.: exp(Sum_{k>=1} binomial(3*k,k) * x^k).

A370327

E.g.f.: exp(Sum_{k>=1} binomial(3*k,k) * x^k).

Terms

    a(0) =1a(1) =3a(2) =39a(3) =801a(4) =22329a(5) =783963a(6) =33142959a(7) =1637118297a(8) =92464016913

External references