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A003712 E.g.f. sin(sin(x)) (odd powers only).
(Formerly M2042)
1
1, -2, 12, -128, 1872, -37600, 990784, -32333824, 1272660224, -59527313920, 3252626013184, -204354574172160, 14594815769038848, -1174376539738169344, 105595092426069327872, -10530693390637550272512 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

abs(a(n)) has e.g.f. sinh(sinh(x)) (odd powers only).

abs(a(n)) is the number of partitions of the set {1, 2, ..., 2*n-1} into an odd number of blocks, each containing an odd number of elements. - Isabel C. Lugo (izzycat(AT)gmail.com), Aug 23 2004

REFERENCES

L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 226, 6th line of table.

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

T. D. Noe, Table of n, a(n) for n=0..50

FORMULA

a(n)=sum(j=1..n+1, (sum(i=0..(2*j-1)/2, (2*i-2*j+1)^(2*n+1)* binomial(2*j-1,i)*(-1)^(n-i-1))/(4^(j-1)*(2*j-1)!))). [Vladimir Kruchinin, Jun 09 2011]

PROG

(Maxima)

a(n):=sum((sum((2*i-2*j+1)^(2*n+1)*binomial(2*j-1, i)*(-1)^(n-i-1), i, 0, (2*j-1)/2)/(4^(j-1)*(2*j-1)!)), j, 1, n+1); [Vladimir Kruchinin, Jun 09 2011]

CROSSREFS

Sequence in context: A173219 A035351 A201470 * A143136 A097629 A014235

Adjacent sequences:  A003709 A003710 A003711 * A003713 A003714 A003715

KEYWORD

sign

AUTHOR

R. H. Hardin (rhhardin(AT)att.net), Simon Plouffe (simon.plouffe(AT)gmail.com)

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Last modified February 15 09:41 EST 2012. Contains 205755 sequences.