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A273878
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Numerator of (2*(n+1)!/(n+2)).
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0
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1, 4, 3, 48, 40, 1440, 1260, 8960, 72576, 7257600, 6652800, 958003200, 889574400, 11623772160, 163459296000, 41845579776000, 39520825344000, 12804747411456000, 12164510040883200, 231704953159680000, 4644631106519040000
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OFFSET
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0,2
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COMMENTS
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The moments, i.e. E(X^n) = int(x^n * p(x), x = 0..infinity) for n > 0, of the probability density function p(x) = 2*x*E(x, 1, 1), see A163931, lead to this sequence.
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LINKS
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FORMULA
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a(n) = numer(2*(n+1)!/(n+2))
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EXAMPLE
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The first few moments of p(x) are: 1, 4/3, 3, 48/5, 40, 1440/7, … .
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MAPLE
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a := proc(n): numer(2*(n+1)!/(n+2)) end: seq(a(n), n=0..20);
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PROG
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(PARI) a(n) = numerator(2*(n+1)!/(n+2)) \\ Felix Fröhlich, Jun 09 2016
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CROSSREFS
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KEYWORD
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nonn,frac,easy
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AUTHOR
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STATUS
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approved
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