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A004117 Numerators of expansion of (1-x)^{-1/3}. +0
4
1, 1, 2, 14, 35, 91, 728, 1976, 5434, 135850, 380380, 1071980, 9111830, 25933670, 74096200, 637227320, 1832028545, 5280552865, 137294374490, 397431084050, 1152550143745, 10043651252635, 29217894553120 (list; graph; listen)
OFFSET

0,3

FORMULA

(1/n!) * prod(k=0, n-1, 3k+1) * 3^A054861(n). - R. Stephan, Mar 13 2004

PROGRAM

(PARI) a(n)=prod(k=1, n, 3*k-2)/n!*3^sum(k=1, n, valuation(k, 3))

CROSSREFS

Cf. A004128.

Cf. A004987, A007559, A047657, A054861, A034689, A053101, A072888.

Sequence in context: A145910 A128126 A134647 this_sequence A135706 A091520 A108597

Adjacent sequences: A004114 A004115 A004116 this_sequence A004118 A004119 A004120

KEYWORD

nonn

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

EXTENSIONS

Fixed typo in formula. - Pontus von Broemssen (pontus.von.bromssen(AT)gmail.com), Nov 25 2008

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Last modified November 25 20:09 EST 2009. Contains 167514 sequences.


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