A357092 E.g.f. satisfies A(x)^A(x) = (1 - x * A(x))^log(1 - x * A(x)).
1, 0, 2, 6, 58, 580, 7568, 119448, 2195772, 46413792, 1106667072, 29403619080, 861570383232, 27600893313552, 959793100481616, 36006430081497120, 1449539553826089360, 62334045415459189248, 2851721291051846833152, 138299011223141244621024
Offset: 0
Keywords
Programs
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PARI
a(n) = sum(k=0, n\2, (2*k)!*(n-k+1)^(k-1)*abs(stirling(n, 2*k, 1))/k!);
Formula
E.g.f. satisfies A(x) * log(A(x)) = log(1 - x * A(x))^2.
a(n) = Sum_{k=0..floor(n/2)} (2*k)! * (n-k+1)^(k-1) * |Stirling1(n,2*k)|/k!.