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A088223
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Coefficient of x^n in g.f.^n is A048286(n).
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2
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1, 2, 3, 12, 93, 1032, 14655, 251688, 5052909, 115925904, 2990175786, 85643490420, 2697023236056, 92629652495280, 3446174110482327, 138077674608686544, 5928227839749416895, 271538262681756156768
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OFFSET
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0,2
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COMMENTS
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LINKS
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FORMULA
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G.f. satisfies: (A(x)-x)^2 = A(x*A(x)). - Paul D. Hanna, Oct 15 2003
a(n) ~ c * 2^(n+1) * n^(n - 1/2 - log(2)/4) / (exp(n) * (log(2))^n), where c = 0.411579248322849751402... (see A240996). - Vaclav Kotesovec, Feb 11 2015
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PROG
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(PARI) {a(n)=local(A, m); if(n<1, n==0, m=1; A=1+x; for(i=1, n, A=subst(A, x, x*A+x*O(x^n))/(A-x) + x); polcoeff(A, 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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