A012374 - OEIS

A012374

sech(tan(x)*sin(x))=1-12/4!*x^4-120/6!*x^6+4368/8!*x^8...

1, 0, -12, -120, 4368, 327360, -762432, -2379861120, -176278202112, 34929443235840, 10554181240931328, -234919154252175360, -852275452306594394112, -157606057918154970808320

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

OFFSET

0,3

LINKS

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

MATHEMATICA

With[{nn=30}, Take[CoefficientList[Series[Sech[Tan[x]Sin[x]], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Jan 31 2016 *)

CROSSREFS

Sequence in context: A221493 A009149 A010570 * A012615 A012559 A009164

Adjacent sequences: A012371 A012372 A012373 * A012375 A012376 A012377

KEYWORD

sign

AUTHOR

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

STATUS

approved