A038080 - OEIS

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A038080

Number of identity trees with 3-colored nodes.

1, 3, 3, 9, 39, 189, 981, 5490, 31674, 189954, 1170126, 7382745, 47494197, 310712808, 2061987642, 13855192866, 94113385437, 645424668666, 4464027720900, 31110200069511, 218292811705458, 1541172223659249 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`0,2`
	LINKS	`Table of n, a(n) for n=0..21.` `Index entries for sequences related to trees`
	FORMULA	`G.f.: B(x)-B^2(x)/2-B(x^2)/2, where B(x) is g.f. for A038079.`
	CROSSREFS	`Cf. A000220. A038077-A038079.` `Sequence in context: A202889 A032086 A100239 * A190960 A216147 A115564` `Adjacent sequences: A038077 A038078 A038079 * A038081 A038082 A038083`
	KEYWORD	`nonn`
	AUTHOR	`Christian G. Bower, Jan 04 1999.`
	STATUS	`approved`

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Last modified May 20 10:38 EDT 2013. Contains 225458 sequences.