A380972 Expansion of e.g.f. (1/x) * Series_Reversion( x * exp(-x*exp(2*x)) ).
1, 1, 7, 76, 1237, 26816, 728899, 23866816, 915129961, 40237778944, 1996402790431, 110351882157056, 6725593733125117, 448106469169905664, 32404532970216803803, 2527793703574203252736, 211589448225820679029969, 18917558526854862344290304, 1799285901282568752019291063
Offset: 0
Keywords
Programs
-
PARI
a(n) = sum(k=0, n, (2*k)^(n-k)*(n+1)^(k-1)*binomial(n, k));
Formula
E.g.f. A(x) satisfies A(x) = exp( x*A(x) * exp(2*x*A(x)) ).
a(n) = Sum_{k=0..n} (2*k)^(n-k) * (n+1)^(k-1) * binomial(n,k).