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A096619
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Number of partitions of a 2*n-element set with exactly two odd blocks.
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0
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1, 10, 136, 2500, 59671, 1786060, 65222431, 2843052040, 145349748316, 8590361117290, 579887365929301, 44257224641241160, 3785653479578940061, 360188281690273321750, 37868568207290527576096
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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FORMULA
| E.g.f.: 1/2*exp(cosh(x)-1)*(sinh(x))^2. More generally, number of partitions of an n-element set with exactly k odd blocks is 1/k!*exp(cosh(x)-1)*(sinh(x))^k.
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CROSSREFS
| Cf. A005046.
Sequence in context: A129803 A065024 A026244 * A003377 A065593 A089834
Adjacent sequences: A096616 A096617 A096618 * A096620 A096621 A096622
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KEYWORD
| easy,nonn
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AUTHOR
| Vladeta Jovovic (vladeta(AT)eunet.rs), Aug 14 2004
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EXTENSIONS
| More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), Nov 16 2004
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