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Search: id:A102286
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| A102286 |
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Total number of odd blocks in all partitions of n-set. |
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+0
3
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| 1, 2, 7, 24, 96, 418, 1989, 10216, 56275, 330424, 2057672, 13532060, 93633021, 679473694, 5156626991, 40824399712, 336406367196, 2879570703510, 25557841113625, 234822774979908, 2230107923204443, 21861817965483016
(list; graph; listen)
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OFFSET
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1,2
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FORMULA
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E.g.f: sinh(x)*exp(exp(x)-1).
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EXAMPLE
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a(3)=7 because we have (123), (1)/23, 12/(3), 13/(2), (1)/(2)/(3); the odd blocks are shown between parentheses.
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MAPLE
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G:=sinh(x)*exp(exp(x)-1): Gser:=series(G, x=0, 30): seq(n!*coeff(Gser, x^n), n=1..25); (Deutsch)
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CROSSREFS
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Cf. A005493, A000296.
Sequence in context: A150423 A150424 A150425 this_sequence A150426 A150427 A150428
Adjacent sequences: A102283 A102284 A102285 this_sequence A102287 A102288 A102289
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KEYWORD
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easy,nonn
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AUTHOR
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Vladeta Jovovic (vladeta(AT)Eunet.yu), Feb 19 2005
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EXTENSIONS
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More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), Mar 04 2005
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