OFFSET
0,2
MATHEMATICA
With[{nn=60}, Take[CoefficientList[Series[Cosh[Sec[x]-Sech[x]], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 4}]] (* Harvey P. Dale, Mar 14 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
EXTENSIONS
More terms from N. J. A. Sloane, Dec 17 2011
STATUS
approved