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A129373 G.f. satisfies: A(x) = (1+x) * A(x^2)*A(x^3)*A(x^4)*...*A(x^n)*... 2
1, 1, 1, 2, 3, 4, 7, 9, 13, 19, 26, 34, 52, 67, 89, 123, 166, 214, 295, 380, 501, 660, 858, 1098, 1461, 1858, 2384, 3072, 3940, 4975, 6410, 8070, 10234, 12946, 16322, 20412, 25848, 32201, 40261, 50287, 62728, 77681, 96885, 119673, 148197, 183108, 225974 (list; graph; refs; listen; history; internal format)
OFFSET

0,4

FORMULA

G.f.: A(x) = Product_{n>=1} (1 + x^n)^A074206(n) where A074206(n) equals the number of ordered factorizations of n.

PROG

(PARI) {a(n)=local(A=1+x); for(i=2, n, A=(1+x)*prod(n=2, i, subst(A, x, x^n+x*O(x^i)))); polcoeff(A, n)}

CROSSREFS

Cf. A074206; A129374, A129375.

Sequence in context: A181385 A188381 A005576 * A139078 A065046 A049709

Adjacent sequences:  A129370 A129371 A129372 * A129374 A129375 A129376

KEYWORD

nonn

AUTHOR

Paul D. Hanna (pauldhanna(AT)juno.com), Apr 12 2007

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Last modified February 15 20:26 EST 2012. Contains 205852 sequences.