A383839 a(n) = [x^n] 1/(1 - n*x) * Product_{k=0..n-1} (1 + k*x)/(1 - k*x).
1, 1, 10, 177, 4576, 156145, 6627006, 336562177, 19906794496, 1344082891761, 102012257669950, 8597688151223281, 796733925564191616, 80516951813773009249, 8812696026991760928766, 1038540275078155878285825, 131107274213106172807069696, 17652158052761888943436783009
Offset: 0
Keywords
Programs
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PARI
a(n) = sum(k=0, n, abs(stirling(n, k, 1))*stirling(k+n, n, 2));
Formula
a(n) = Sum_{k=0..n} |Stirling1(n,k)| * Stirling2(k+n,n).