This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A102072 E.g.f. sec(arcsinh(x)) = cosec(arccosh(x)) (even powers only). 6
 1, 1, 1, 25, -415, 35825, -3356575, 492769225, -96314333375, 24701457990625, -8006683308349375, 3204344303824405625, -1551453429875871169375, 893896220277392770140625, -604413346665043743464609375 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 LINKS EXAMPLE sec(arcsinh(x)) = 1 + x^2/2 + x^4/4! + 25x^6/6! - 415x^8/8! +... sech(arcsin(x)) = 1 - x^2/2 + x^4/4! - 25x^6/6! - 415x^8/8! -... MATHEMATICA With[{nn=30}, Take[CoefficientList[Series[Sec[ArcSinh[x]], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Aug 15 2016 *) CROSSREFS Sequence in context: A025980 A025978 A028037 * A022845 A023952 A025991 Adjacent sequences:  A102069 A102070 A102071 * A102073 A102074 A102075 KEYWORD sign AUTHOR Ralf Stephan, Dec 31 2004 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified October 17 02:04 EDT 2019. Contains 328106 sequences. (Running on oeis4.)