A368450 Expansion of e.g.f. exp(x) / (1 + log(1 - 3*x)/3).
1, 2, 8, 61, 695, 10310, 187024, 4002131, 98593949, 2746565218, 85333213856, 2924626915529, 109588276298995, 4456269669580742, 195418762093000328, 9192090435429906463, 461630086359185798777, 24651183861530752336994, 1394716088179233110318104
Offset: 0
Keywords
Programs
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PARI
a_vector(n) = my(v=vector(n+1)); for(i=0, n, v[i+1]=1+sum(j=1, i, 3^(j-1)*(j-1)!*binomial(i, j)*v[i-j+1])); v;
Formula
a(n) = 1 + Sum_{k=1..n} 3^(k-1) * (k-1)! * binomial(n,k) * a(n-k).