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A368011
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Expansion of (1/x) * Series_Reversion( x * ((1-x)^5-x^5) ).
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2
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1, 5, 40, 385, 4095, 46377, 548380, 6691620, 83637450, 1065311665, 13777916774, 180451354720, 2388503030675, 31900445734050, 429369814375480, 5818270533841408, 79309912829992350, 1086768622818959100, 14961519902879613700, 206839961042385226110
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OFFSET
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0,2
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LINKS
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FORMULA
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a(n) = (1/(n+1)) * Sum_{k=0..floor(n/5)} binomial(n+k,k) * binomial(6*n+4,n-5*k).
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PROG
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(PARI) my(N=30, x='x+O('x^N)); Vec(serreverse(x*((1-x)^5-x^5))/x)
(PARI) a(n) = sum(k=0, n\5, binomial(n+k, k)*binomial(6*n+4, n-5*k))/(n+1);
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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