G.f.: Sum_{n>=0} n! * 2^(n*(n-1)/2) * x^n / Product_{k=1..n} (1 + k*2^k*x).

A182507

G.f.: Sum_{n>=0} n! * 2^(n*(n-1)/2) * x^n / Product_{k=1..n} (1 + k*2^k*x).

Terms

    a(0) =1a(1) =1a(2) =2a(3) =12a(4) =232a(5) =12848a(6) =1858464a(7) =663242944a(8) =562426769024

External references