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A090586
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Denominator of Sum/Product of first n numbers.
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11
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1, 2, 1, 12, 8, 240, 180, 1120, 8064, 725760, 604800, 79833600, 68428800, 830269440, 10897286400, 2615348736000, 2324754432000, 711374856192000, 640237370572800, 11585247657984000, 221172909834240000, 102181884343418880000, 93666727314800640000
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OFFSET
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1,2
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COMMENTS
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a(p-1) = 2*A000142(p-2) for odd primes.
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LINKS
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MAPLE
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seq(denom((n+1)/(2*(n-1)!)), n=1..25); # Robert Israel, Oct 14 2018
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MATHEMATICA
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Table[Denominator[(n + 1) / (2 (n - 1)!)], {n, 25}] (* Vincenzo Librandi, Oct 15 2018 *)
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PROG
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(Magma) [Denominator(n + 1) / (2*Factorial(n - 1)): n in [1..30]]; // Vincenzo Librandi, Oct 15 2018
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CROSSREFS
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KEYWORD
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nonn,frac
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AUTHOR
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STATUS
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approved
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