A013510 arcsinh(sec(x)-sech(x))=2/2!*x^2+2/6!*x^6+65762/10!*x^10...

2, 2, 65762, -418934878, 14989881142082, -1159565898643479358, 201365713271464069504802, -65359378924390295271709921438, 36977332162396361445823162953505922, -33930775864190349375460255092763386069118, 47994298632572575541623806754970220542333977442

Offset

0,1

Links

Table of n, a(n) for n=0..10.

Mathematica

With[{nn=50}, Take[CoefficientList[Series[ArcSinh[Sec[x]-Sech[x]], {x, 0, nn}], x]Range[0, nn]!, {3, -1, 4}]] (* Harvey P. Dale, Jan 22 2013 *)

Crossrefs

Sequence in context: A079237 A262060 A243411 * A013504 A230807 A173012

Adjacent sequences: A013507 A013508 A013509 * A013511 A013512 A013513

Keyword

sign

Author

Patrick Demichel (patrick.demichel(AT)hp.com)

Extensions

More terms from N. J. A. Sloane, Dec 17 2011

Status

approved