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A113551
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a(n) = product of next n even numbers beginning with n if n is even, otherwise product of next n odd numbers beginning with n.
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8
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1, 8, 105, 1920, 45045, 1290240, 43648605, 1703116800, 75293843625, 3719607091200, 203067496256625, 12140797545676800, 788917222956988125, 55362036808286208000, 4172583192219510193125, 336158287499913854976000
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OFFSET
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1,2
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LINKS
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FORMULA
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EXAMPLE
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a(3) = 3*5*7 = 105, a(4) = 4*6*8*10 = 1920.
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MAPLE
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MATHEMATICA
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Do[Print[Product[n + 2i, {i, 0, n - 1}]], {n, 1, 20}] (* Tracy Poff (tracy.poff(AT)gmail.com), Dec 31 2005 *)
Table[Times@@Range[n, 3n-2, 2], {n, 20}] (* or *) Table[(2^n Gamma[(3n)/2])/Gamma[n/2], {n, 20}] (* Harvey P. Dale, Nov 28 2022 *)
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PROG
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(PARI) for(n=1, 25, print1(prod(k=0, n-1, n+2*k), ", ")) \\ G. C. Greubel, Sep 30 2017
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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EXTENSIONS
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More terms from Tracy Poff (tracy.poff(AT)gmail.com), Dec 31 2005
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STATUS
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approved
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