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A357393
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E.g.f. satisfies A(x) = -log(1 - x * exp(3 * A(x))).
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1
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0, 1, 7, 110, 2730, 93024, 4037880, 213127200, 13253058000, 948964262400, 76899763100160, 6957624460550400, 695236239163065600, 76043127767523840000, 9036546669251861760000, 1159342449440429270016000, 159708538424128885551360000, 23512778013219939149561856000
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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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E.g.f. satisfies A(x) = log(1 + x * exp(4 * A(x))).
a(n) = Sum_{k=1..n} (3 * n)^(k-1) * |Stirling1(n,k)|.
a(n) = Sum_{k=1..n} (4 * n)^(k-1) * Stirling1(n,k).
a(n) = Product_{k=3*n+1..4*n-1} k = (4*n-1)!/(3*n)! for n > 0.
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PROG
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(PARI) a(n) = sum(k=1, n, (3*n)^(k-1)*abs(stirling(n, k, 1)));
(PARI) a(n) = sum(k=1, n, (4*n)^(k-1)*stirling(n, k, 1));
(PARI) a(n) = if(n==0, 0, (4*n-1)!/(3*n)!);
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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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