A081921 - OEIS

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A081921

Expansion of exp(3x)/sqrt(1-x^2).

1, 3, 10, 36, 144, 648, 3384, 20520, 145728, 1181952, 10917504, 111601152, 1265777280, 15544566144, 208320719616, 2980582728192, 46020833427456, 751100760576000, 13121167636058112, 240473024248393728 (list; graph; refs; listen; history; internal format)

	OFFSET	`0,2`
	COMMENTS	`Binomial transform of A081920`
	FORMULA	`E.g.f. exp(3x)/sqrt(1-x^2)` `a(n) = 3^nn!Sum_{k=0..floor(n/2)} binomial(2k, k)/(n-2k)!/36^k. - Vladeta Jovovic (vladeta(AT)eunet.rs), Oct 11 2003`
	CROSSREFS	`Cf. A081922.` `Sequence in context: A129247 A162162 A149042 * A165792 A010373 A104603` `Adjacent sequences: A081918 A081919 A081920 * A081922 A081923 A081924`
	KEYWORD	`easy,nonn`
	AUTHOR	`Paul Barry (pbarry(AT)wit.ie), Apr 01 2003`

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Last modified February 17 11:46 EST 2012. Contains 206011 sequences.