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A082292
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a(n) = (2n+1) * (2n)! / sqrt(4*(n+1)*Product_{k=1..2n+1} lcm(k, 2n+2-k)).
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1
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1, 1, 2, 12, 4, 8, 72, 160, 16, 3456, 32, 1792, 129600, 1024, 128, 1492992, 256, 2048000, 18289152, 180224, 1024, 573308928, 1280000, 1703936, 241864704, 719323136, 8192, 64497254400000, 16384, 33554432, 234125033472, 142606336
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OFFSET
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2,3
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LINKS
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MATHEMATICA
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Table[((2n+1)(2n)!)/Sqrt[4(n+1)Product[LCM[k, 2n+2-k], {k, 2n+1}]], {n, 2, 40}] (* Harvey P. Dale, Aug 01 2020 *)
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PROG
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(PARI) for(i=2, 20, n=i*2+1; p=1; for(k=1, n, p=p*lcm(k, n+1-k)); print1((2*i+1)*(2*i)!/sqrtint(4*(i+1)*p)", "))
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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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