The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A012457 sin(arctan(x)^2)=2/2!*x^2-16/4!*x^4+248/6!*x^6-3456/8!*x^8... 2
 2, -16, 248, -3456, -406368, 123982080, -31807263360, 9173875200000, -3114459024453120, 1251070155460915200, -591321674803999426560, 326012628782956574638080, -207713640106463567695994880 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 LINKS Robert Israel, Table of n, a(n) for n = 0..223 FORMULA Sum_{n>=0} a(n) x^(2*n+2)/(2*n+2)! = sin(arctan(x)^2). - Robert Israel, Apr 04 2016 MAPLE S:= series(g, x, 52): seq(coeff(S, x, 2*j)*(2*j)!, j=1..25); # Robert Israel, Apr 04 2016 MATHEMATICA With[{nn=30}, Take[CoefficientList[Series[Sin[ArcTan[x]^2], {x, 0, nn}], x] Range[0, nn]!, {3, -1, 2}]] (* Harvey P. Dale, Aug 20 2014 *) CROSSREFS Sequence in context: A009233 A188560 A012462 * A138764 A009833 A009044 Adjacent sequences:  A012454 A012455 A012456 * A012458 A012459 A012460 KEYWORD sign AUTHOR Patrick Demichel (patrick.demichel(AT)hp.com) EXTENSIONS Definition clarified by Harvey P. Dale, Aug 20 2014 STATUS approved

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

Last modified May 28 07:30 EDT 2022. Contains 354112 sequences. (Running on oeis4.)