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A047677
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Row 2 of square array defined in A047675: 2*n!*(n+1)!.
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2
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2, 4, 24, 288, 5760, 172800, 7257600, 406425600, 29262643200, 2633637888000, 289700167680000, 38240422133760000, 5965505852866560000, 1085722065221713920000, 228001633696559923200000, 54720392087174381568000000, 14883946647711431786496000000
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OFFSET
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0,1
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COMMENTS
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LINKS
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MAPLE
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a:= proc(n) a(n):= `if`(n=0, 2, n*(n+1) * a(n-1)) end:
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MATHEMATICA
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2*Times@@@Partition[Range[0, 20]!, 2, 1] (* Harvey P. Dale, Sep 25 2017 *)
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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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