A012032 sec(sin(sinh(x)))=1+1/2!*x^2+5/4!*x^4+13/6!*x^6-1303/8!*x^8...

1, 1, 5, 13, -1303, -97351, -5539667, -182565627, 23677748561, 8153921374705, 1571128609968341, 190412412110488701, -16146953133290647751, -22882305147029329939799

Offset

0,3

Links

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

Mathematica

With[{nn=30}, Take[CoefficientList[Series[Sec[Sin[Sinh[x]]], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Mar 18 2025 *)

Crossrefs

Sequence in context: A396335 A153374 A247789 * A121228 A201260 A012173

Adjacent sequences: A012029 A012030 A012031 * A012033 A012034 A012035

Keyword

sign

Author

Patrick Demichel

Status

approved