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A072118
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a(n) = (2*n)!/core(n!)^2/(n+1) where core(x) is the squarefree part of x.
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0
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1, 2, 5, 224, 672, 2737152, 8895744, 474439680, 130660687872, 4513732853760000, 15798064988160000, 894413525483520000, 3194334019584000000, 27610545531676262400000, 8107146431738442547200000
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OFFSET
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1,2
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LINKS
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PROG
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(PARI) for(n=1, 50, print1((2*n)!/core(n!)^2/(n+1), ", "))
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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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STATUS
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approved
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