A012568 - OEIS

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A012568

arctanh(sinh(x)*cos(x))=x-20/5!*x^5-560/7!*x^7-7920/9!*x^9...

1, 0, -20, -560, -7920, 1034880, 172569280, 12339608320, -1902800305920, -1037015219466240, -208832669083243520, 24402030281141555200, 43057075784745711636480, 18939654540025835056496640

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,3

LINKS

Table of n, a(n) for n=0..13.

FORMULA

a(n) = A009357(2n+1). - R. J. Mathar, Mar 17 2007

MATHEMATICA

With[{nn=30}, Take[CoefficientList[Series[ArcTanh[Sinh[x]Cos[x]], {x, 0, nn}], x] Range[ 0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, Jun 22 2022 *)

CROSSREFS

Cf. A009357.

Sequence in context: A210486 A047682 A231249 * A259057 A184123 A027407

Adjacent sequences: A012565 A012566 A012567 * A012569 A012570 A012571

KEYWORD

sign

AUTHOR

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

STATUS

approved