A077921 - OEIS

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A077921

Expansion of (1-x)^(-1)/(1+2*x-x^2).

1, -1, 4, -8, 21, -49, 120, -288, 697, -1681, 4060, -9800, 23661, -57121, 137904, -332928, 803761, -1940449, 4684660, -11309768, 27304197, -65918161, 159140520, -384199200, 927538921, -2239277041, 5406093004, -13051463048, 31509019101, -76069501249, 183648021600 (list; graph; refs; listen; history; internal format)

	OFFSET	`0,3`
	LINKS	`Index entries for two-way infinite sequences`
	FORMULA	`Partial sums of sequence of signed Pell numbers (-1)^n*A000129(n). - Paul Barry (pbarry(AT)wit.ie), May 09 2003` `G.f.: 1/((1-x)(1+2x-x^2)).`
	MATHEMATICA	`CoefficientList[Series[(1/(1-x))/(1+2x-x^2), {x, 0, 50}], x] (* From Harvey P. Dale, Mar 20 2011 *)`
	CROSSREFS	`-a(-3-n)=A048739(n).` `Sequence in context: A061256 A180608 * A097076 A003608 A129794 A064503` `Adjacent sequences: A077918 A077919 A077920 * A077922 A077923 A077924`
	KEYWORD	`sign`
	AUTHOR	`N. J. A. Sloane (njas(AT)research.att.com), Nov 17 2002`

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Last modified February 17 13:08 EST 2012. Contains 206027 sequences.