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A067622 Consider the power series (x + 1)^(1/3) = 1 + x/3-x^2/9 + 5x^3/81 + ...; sequence gives numerators of coefficients. 2
1, 1, -1, 5, -10, 22, -154, 374, -935, 21505, -55913, 147407, -1179256, 3174920, -8617640, 70664648, -194327782, 537259162, -13431479050, 37466757350, -104906920580, 884215473460, -2491879970660, 7042269482300, -59859290599550 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Table of n, a(n) for n=0..24.

FORMULA

a(n) =(-1)^n*A004990(n)*A067623(n)/A000244(n); ignoring signs, a(n) =A038502(A004990(n)) =A038502(A034164(n-2)). a(n)'s sign is (-1)^(n+1) if n>0.

MAPLE

s := convert(taylor((x+1)^(1/3), x, 50), polynom): for n from 0 to 50 do printf(`%a, `, abs(numer(coeff(s, x, n)))) od;

CROSSREFS

Denominators are A067623.

Sequence in context: A132461 A087746 A064694 * A196240 A175661 A197174

Adjacent sequences:  A067619 A067620 A067621 * A067623 A067624 A067625

KEYWORD

sign,frac

AUTHOR

Benoit Cloitre, Feb 02 2002

EXTENSIONS

Edited by Henry Bottomley and James A. Sellers, Feb 11 2002

STATUS

approved

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Last modified June 20 00:15 EDT 2013. Contains 226416 sequences.