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A067622
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Consider the power series (x + 1)^(1/3) = 1 + x/3-x^2/9 + 5x^3/81 + ...; sequence gives numerators of coefficients.
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2
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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
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OFFSET
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0,4
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LINKS
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Table of n, a(n) for n=0..24.
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FORMULA
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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.
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MAPLE
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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;
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CROSSREFS
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Denominators are A067623.
Sequence in context: A132461 A087746 A064694 * A196240 A175661 A197174
Adjacent sequences: A067619 A067620 A067621 * A067623 A067624 A067625
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KEYWORD
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sign,frac
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AUTHOR
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Benoit Cloitre, Feb 02 2002
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EXTENSIONS
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Edited by Henry Bottomley and James A. Sellers, Feb 11 2002
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STATUS
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approved
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