G.f.: exp( Sum_{n>=1} A206154(n)*x^n/n ), where A206154(n) = Sum_{k=0..n} binomial(n,k)^(k+2).

A206153

G.f.: exp( Sum_{n>=1} A206154(n)*x^n/n ), where A206154(n) = Sum_{k=0..n} binomial(n,k)^(k+2).

Terms

    a(0) =1a(1) =2a(2) =7a(3) =48a(4) =693a(5) =26632a(6) =2542514a(7) =533442978a(8) =278979307990

External references