A367847 Expansion of e.g.f. 1/(1 - x + log(1 - 4*x)).
1, 5, 66, 1358, 37592, 1304536, 54384080, 2646247152, 147186205056, 9210766696320, 640472632680192, 48989958019395840, 4087959251421060096, 369547591764702870528, 35976590549993421907968, 3752609987262290143082496, 417518648351593243448279040
Offset: 0
Keywords
Programs
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PARI
a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=i*v[i]+sum(j=1, i, 4^j*(j-1)!*binomial(i, j)*v[i-j+1])); v;
Formula
a(0) = 1; a(n) = n * a(n-1) + Sum_{k=1..n} 4^k * (k-1)! * binomial(n,k) * a(n-k).