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A144008
E.g.f. satisfies: A'(x) = (1 + x*A(x))^3 with A(0)=1.
5
1, 1, 3, 12, 69, 504, 4455, 46512, 558873, 7599744, 115401915, 1935368640, 35529636285, 708677828352, 15261101987391, 352891976935680, 8721014464717425, 229385791746109440, 6398158947146344755
OFFSET
0,3
COMMENTS
Compare the definition of the e.g.f. A(x) to the trivial statement:
if F(x) = 1/(1-x) then F'(x) = (1 + x*F(x))^2.
LINKS
FORMULA
E.g.f. satisfies: A(x) = 1 + Integral (1 + x*A(x))^3 dx.
a(n) ~ n^n / (exp(n) * r^(n+2)), where r = 0.628168728379601723852469... - Vaclav Kotesovec, Feb 24 2014
PROG
(PARI) {a(n)=local(A=1+x); for(i=0, n, A=1+intformal((1+x*A+x*O(x^n))^3)); n!*polcoeff(A, n)}
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Sep 10 2008
STATUS
approved