id:A098276 - OEIS Search Results

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Difference between the number of even reduced Latin rectangles of size 3 X n and the number of odd ones.

+0
1

1, 0, 2, 0, 72, -320, 3600, -32256, 344960, -3926016, 48625920, -648243200, 9270125568, -141579509760, 2300668418048, -39642283376640, 722055883161600, -13863472939925504, 279868860012625920 (list; graph; listen)

	OFFSET	`1,3`
	LINKS	`J. Zeng, The generating function for the difference in even and odd three-line latin rectangles, Ann. Sci. Math. Quebec 20/1 (1996) 105-108.`
	FORMULA	`E.g.f.: -1 + [(1-x)^2/(1+x)+x/(1+x)^2] * exp(2x).`
	PROGRAM	`(PARI) a(n)=polcoeff(serlaplace(exp(2x)((1-x)^2/(1+x)+x/(1+x)^2)), n)` `(PARI) a(n)=(-1)^(n-1)(n-2)n!/2polcoeff(Ser(exp(2(atanh(x)-x))), n)`
	CROSSREFS	`Cf. A000186.` `Adjacent sequences: A098273 A098274 A098275 this_sequence A098277 A098278 A098279` `Sequence in context: A012420 A140800 A012694 this_sequence A013553 A030129 A012647`
	KEYWORD	`sign,easy`
	AUTHOR	`Ralf Stephan, Sep 06 2004`

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Last modified October 7 14:39 EDT 2008. Contains 144666 sequences.

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