A368287 Expansion of e.g.f. exp(-2*x) / (1 + 2*log(1 - x)).
1, 0, 6, 32, 356, 4456, 68096, 1211136, 24625408, 563266240, 14315378880, 400206928128, 12205482237824, 403262088466688, 14348434923733504, 546996936260529152, 22243031618999642112, 961019064912965103616, 43963636798214215278592
Offset: 0
Keywords
Programs
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PARI
a_vector(n) = my(v=vector(n+1)); for(i=0, n, v[i+1]=(-2)^i+2*sum(j=1, i, (j-1)!*binomial(i, j)*v[i-j+1])); v;
Formula
a(n) = (-2)^n + 2 * Sum_{k=1..n} (k-1)! * binomial(n,k) * a(n-k).