login
A012167
cosh(tan(arcsinh(x)))=1+1/2!*x^2+5/4!*x^4+61/6!*x^6+937/8!*x^8...
2
1, 1, 5, 61, 937, 41881, 259181, 225924245, -25529526319, 8376428366257, -2542034772205739, 1049519923013252461, -506849756298097166215, 294020276106503596553801, -199395048123852155910464323
OFFSET
0,3
MATHEMATICA
With[{nn=30}, Take[CoefficientList[Series[Cosh[Tan[ArcSinh[x]]], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Aug 25 2020 *)
CROSSREFS
Sequence in context: A064328 A363867 A012060 * A162167 A134282 A146760
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved