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Search: id:A088312
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| A088312 |
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Number of sets of lists (cf. A000262) with even number of lists. |
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+0
1
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| 1, 6, 37, 260, 2101, 19362, 201097, 2326536, 29668681, 413257790, 6238931821, 101415565836
(list; graph; listen)
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OFFSET
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2,2
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LINKS
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N. Heninger, E. M. Rains and N. J. A. Sloane, On the Integrality of n-th Roots of Generating Functions, J. Combinatorial Theory, Series A, 113 (2006), 1732-1745.
N. J. A. Sloane, LAH transform
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FORMULA
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E.g.f.: cosh(x/(1-x)). a(n) = Sum_{k=1.. floor(n/2)} n!/(2*k)!*binomial(n-1, 2*k-1).
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CROSSREFS
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Cf. A027187, A024429, A024430, A001710.
Sequence in context: A073013 A140712 A079751 this_sequence A012364 A012719 A036358
Adjacent sequences: A088309 A088310 A088311 this_sequence A088313 A088314 A088315
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KEYWORD
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nonn
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AUTHOR
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Vladeta Jovovic (vladeta(AT)eunet.rs), Nov 05 2003
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