A009713 - OEIS

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A009713

Expansion of tan(tanh(tan(x))).

1, 2, 8, -176, -16384, -969728, -32455680, 4303626240, 1468506210304, 269552004300800, 24649152071991296, -7396863878894714880, -5630959968640999358464, -2114449853843696991076352 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`0,2`
	LINKS	`Table of n, a(n) for n=0..13.`
	MATHEMATICA	`With[{nn=30}, Take[CoefficientList[Series[Tan[Tanh[Tan[x]]], {x, 0, nn}], x] Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, Aug 03 2016 *)`
	CROSSREFS	`Sequence in context: A076548 A167009 A350808 * A265597 A213200 A317794` `Adjacent sequences: A009710 A009711 A009712 * A009714 A009715 A009716`
	KEYWORD	`sign`
	AUTHOR	`R. H. Hardin`
	EXTENSIONS	`Extended with signs by Olivier Gérard, Mar 15 1997` `Prior Mathematica program replaced by Harvey P. Dale, Aug 03 2016`
	STATUS	`approved`

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Last modified December 5 04:31 EST 2023. Contains 367574 sequences. (Running on oeis4.)