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A013483 E.g.f.: sin(cos(x)-sech(x)) (even powers only). 1
0, 0, -4, 60, -1384, 50520, -2333164, 98460180, 2691348656, -2502877578960, 816953866876076, -250462447769994900, 80927047278922241096, -28429551522622456235640, 10951929595731882160395716 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..50

EXAMPLE

sin(cos(x)-sech(x))=0*x^0+0*x^2-4/4!*x^4+60/6!*x^6-1384/8!*x^8+50520/10!*x^10...

MATHEMATICA

With[{nn=30}, Take[CoefficientList[Series[Sin[Cos[x]-Sech[x]], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Mar 09 2014 *)

CROSSREFS

Sequence in context: A208890 A325154 A013486 * A013484 A013485 A324959

Adjacent sequences:  A013480 A013481 A013482 * A013484 A013485 A013486

KEYWORD

sign

AUTHOR

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

EXTENSIONS

Name clarified, a(0)=a(1)=1 prepended, Joerg Arndt, Mar 09 2014

STATUS

approved

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Last modified December 1 14:10 EST 2021. Contains 349430 sequences. (Running on oeis4.)