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A012692
sech(tanh(x)*cos(x))=1-1/2!*x^2+25/4!*x^4-1057/6!*x^6+81905/8!*x^8...
0
1, -1, 25, -1057, 81905, -10280289, 1887120585, -476966767617, 158890850697185, -67468163508862017, 35571148438980847225, -22799419589275221917281, 17459463801481355245128145
OFFSET
0,3
MATHEMATICA
With[{nn=30}, Take[CoefficientList[Series[Sech[Tanh[x]Cos[x]], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Apr 13 2019 *)
CROSSREFS
Sequence in context: A367974 A167257 A346160 * A193121 A246923 A066852
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved