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Search: id:A037963
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| A037963 |
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(n+5)!*n^2*(3*n^3+10*n^2+5*n-2)/11520. |
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+0
2
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| 0, 1, 126, 5796, 186480, 5103000, 129230640, 3162075840, 76592355840, 1863435974400, 45950224320000, 1155068769254400, 29708792431718400, 783699448602470400, 21234672840116736000, 591499300737945600000
(list; graph; listen)
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OFFSET
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0,3
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COMMENT
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For n>=1, a(n) is equal to the number of surjections from {1,2,...,n+5} onto {1,2,...,n}. - Aleksandar M. Janjic and Milan R. Janjic (agnus(AT)blic.net), Feb 24 2007
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REFERENCES
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The right-hand side of a binomial coefficient identity in H. W. Gould, Combinatorial Identities, Morgantown, 1972.
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LINKS
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Milan Janjic, Enumerative Formulas for Some Functions on Finite Sets
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CROSSREFS
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Sequence in context: A086024 A036403 A140902 this_sequence A156931 A075919 A121004
Adjacent sequences: A037960 A037961 A037962 this_sequence A037964 A037965 A037966
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KEYWORD
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nonn
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AUTHOR
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N. J. A. Sloane (njas(AT)research.att.com).
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