

A012339


E.g.f.: sech(arcsin(x)*sin(x))=112/4!*x^4+6160/8!*x^8120960/10!*x^10...


1



1, 0, 12, 0, 6160, 120960, 30419136, 720079360, 289764450560, 67943999090688, 22346350979320832, 79039716551606272, 455312101897953210368, 1387404550704064289013760, 763348964181211012935499776, 349778941309176227928741642240
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OFFSET

0,3


LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..100


MATHEMATICA

With[{nn=40}, Take[CoefficientList[Series[Sech[ArcSin[x]Sin[x]], {x, 0, nn}], x] Range[0, nn]!, {1, 1, 2}]] Harvey P. Dale, May 17 2012


CROSSREFS

Sequence in context: A120954 A265087 A012337 * A012448 A012338 A012453
Adjacent sequences: A012336 A012337 A012338 * A012340 A012341 A012342


KEYWORD

sign


AUTHOR

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


EXTENSIONS

Definition clarified by and more terms from Harvey P. Dale, May 17 2012


STATUS

approved



