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A013031
sec(sinh(x)+sin(x))=1+4/2!*x^2+80/4!*x^4+3928/6!*x^6+359040/8!*x^8...
0
1, 4, 80, 3928, 359040, 52717856, 11352019840, 3370401007488, 1319560185804800, 658698869874201088, 408325769541831280640, 307740770628961995577344, 277115224743231975378370560
OFFSET
0,2
MATHEMATICA
With[{nn=30}, Take[CoefficientList[Series[Sec[Sinh[x]+Sin[x]], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Aug 26 2013 *)
CROSSREFS
Sequence in context: A214298 A102063 A002436 * A012923 A012922 A013090
KEYWORD
nonn
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved