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A356884
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E.g.f. satisfies A(x)^A(x) = 1/(1 - x*A(x))^x.
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2
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1, 0, 2, 3, 20, 150, 1254, 14280, 190000, 2863728, 49465080, 954312480, 20303200488, 473604468480, 12007399511184, 328671680500800, 9663415159357440, 303695188102656000, 10159173955921651776, 360424299614544829440, 13517056067747847719040
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OFFSET
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0,3
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LINKS
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FORMULA
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a(n) = n! * Sum_{k=0..floor(n/2)} (n-2*k+1)^(k-1) * |Stirling1(n-k,k)|/(n-k)!.
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PROG
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(PARI) a(n) = n!*sum(k=0, n\2, (n-2*k+1)^(k-1)*abs(stirling(n-k, k, 1))/(n-k)!);
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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