A087213 - OEIS

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A087213

Expansion of (1+x-4x^2)/((1+x)(1-4x^2)).

1, 0, 0, 4, -4, 20, -20, 84, -84, 340, -340, 1364, -1364, 5460, -5460, 21844, -21844, 87380, -87380, 349524, -349524, 1398100, -1398100, 5592404, -5592404, 22369620, -22369620, 89478484, -89478484, 357913940, -357913940, 1431655764, -1431655764 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`0,4`
	COMMENTS	`Binomial transform is A046717 (with extra leading 1). a(2n+1)=A002450(n)=A001045(2n). a(2n+2)=-A002450(n)=-A001045(2n).`
	LINKS	`Table of n, a(n) for n=0..32.`
	FORMULA	`a(n)=2^n/6-(-2)^n/2+4(-1)^n/3`
	CROSSREFS	`Sequence in context: A133039 A177117 A035413 * A117857 A165559 A180967` `Adjacent sequences: A087210 A087211 A087212 * A087214 A087215 A087216`
	KEYWORD	`easy,sign`
	AUTHOR	`Paul Barry, Aug 26 2003`
	STATUS	`approved`

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Last modified May 18 17:41 EDT 2013. Contains 225422 sequences.