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Search: id:A082134
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| A082134 |
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Expansion of xexp(3x)cosh(x). |
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+0
7
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| 0, 1, 6, 30, 144, 680, 3168, 14560, 66048, 296064, 1313280, 5772800, 25178112, 109078528, 469819392, 2013388800, 8590196736, 36507779072, 154620002304, 652837519360, 2748784312320, 11544883101696, 48378534690816
(list; graph; listen)
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OFFSET
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0,3
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COMMENT
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Binomial transform of A082133. 3rd binomial transform of (0,1,0,3,0,5,0,7,....)
Let P(A) be the power set of an n-element set A. Then a(n) = the sum of the size of the intersection of x and y for every {x,y} of P(A). - Ross La Haye (rlahaye(AT)new.rr.com), Dec 30 2007
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FORMULA
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a(n)=n(2^(n-1)+4^(n-1))/2 E.g.f. xexp(3x)cosh(x)
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CROSSREFS
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Cf. A057711, A082135.
Adjacent sequences: A082131 A082132 A082133 this_sequence A082135 A082136 A082137
Sequence in context: A137400 A026749 A003279 this_sequence A030192 A026376 A026899
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KEYWORD
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easy,nonn
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AUTHOR
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Paul Barry (pbarry(AT)wit.ie), Apr 06 2003
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