E.g.f.: A(x) = exp( Sum_{n>=1} 2^(n(n-1)/2) * x^n/n ).

A171777

E.g.f.: A(x) = exp( Sum_{n>=1} 2^(n(n-1)/2) * x^n/n ).

Terms

    a(0) =1a(1) =1a(2) =3a(3) =23a(4) =473a(5) =27057a(6) =4102027a(7) =1539365191

External references