A013504 sin(sec(x)-sech(x))=2/2!*x^2+2/6!*x^6-176158/10!*x^10...

2, 2, -176158, -1468303198, -23972242057918, -659094144077286718, -17783195610659060805598, 2907154691514883581324639842, 1898415071310817291664803882934402, 1068476725686706833449994431404467473282, 726967725616567229436454165277652418918762082

Offset

0,1

Links

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

Mathematica

With[{nn=50}, Take[CoefficientList[Series[Sin[Sec[x]-Sech[x]], {x, 0, nn}], x] Range[0, nn]!, {3, -1, 4}]] (* Harvey P. Dale, May 28 2021 *)

Crossrefs

Sequence in context: A262060 A243411 A013510 * A230807 A173012 A083925

Adjacent sequences: A013501 A013502 A013503 * A013505 A013506 A013507

Keyword

sign

Author

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

Extensions

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

Status

approved