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A248045
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(2*(n-1))! * (2*n-1)! / (n * (n-1)!^3).
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6
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1, 6, 120, 4200, 211680, 13970880, 1141620480, 111307996800, 12614906304000, 1629845894476800, 236475822507724800, 38072607423743692800, 6735922851893114880000, 1299070835722243584000000, 271245990498804460339200000, 60962536364606302461235200000
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OFFSET
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1,2
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COMMENTS
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LINKS
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FORMULA
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n*a(n) = 4*(2*n-1)*(2*n-3)*a(n-1). - R. J. Mathar, Oct 07 2014
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PROG
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(Haskell)
a248045 n = a000891 (n - 1) * a000142 n
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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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