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Search: id:A037962
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| A037962 |
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(n+4)!*n*(15*n^3+30*n^2+5*n-2)/5760. |
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+0
2
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| 0, 1, 62, 1806, 40824, 834120, 16435440, 322494480, 6411968640, 130456085760, 2731586457600, 59056027430400, 1320663933388800, 30575780537702400, 733062897120153600, 18198613875746304000
(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+4} 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: A157499 A103428 A115504 this_sequence A017778 A035726 A017725
Adjacent sequences: A037959 A037960 A037961 this_sequence A037963 A037964 A037965
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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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