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A013451 E.g.f.: exp(tan(x)-tanh(x))=1+4/3!*x^3+160/6!*x^6+544/7!*x^7+17920/9!*x^9... 0
1, 0, 0, 4, 0, 0, 160, 544, 0, 17920, 261120, 707584, 3942400, 149360640, 1538068480, 5242548224, 111522611200, 2782416732160, 25458261360640, 166243180478464, 5279051703910400, 109528131284500480 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Table of n, a(n) for n=0..21.

MATHEMATICA

With[{nn=30}, CoefficientList[Series[Exp[Tan[x]-Tanh[x]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Jun 19 2013 *)

CROSSREFS

Sequence in context: A192057 A054376 A071608 * A013462 A326862 A222325

Adjacent sequences:  A013448 A013449 A013450 * A013452 A013453 A013454

KEYWORD

nonn

AUTHOR

Patrick Demichel (patrick.demichel(AT)hp.com)

EXTENSIONS

Definition clarified by Harvey P. Dale, Jun 19 2013

STATUS

approved

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Last modified December 9 07:21 EST 2021. Contains 349627 sequences. (Running on oeis4.)