This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A024343 Expansion of e.g.f. sin(x^2), coefficients of x^(4*n + 2). 2
 2, -120, 30240, -17297280, 17643225600, -28158588057600, 64764752532480000, -202843204931727360000, 830034394580628357120000, -4299578163927654889881600000, 27500101936481280675682713600000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS Absolute values are coefficients of expansion of sinh(x^2). LINKS FORMULA (-1)^n * (4n+2)! / (2n+1)!. E.g.f.: Sin[ x^2 ] (* [ x^(4n+2) ] *) a(n) = 2 * A009564(n). - Sean A. Irvine, Jul 01 2019 PROG (PARI) a(n)=polcoeff(serlaplace(sin(x^2)), 4*n+2) (PARI) a(n)=(-1)^n*(4*n+2)!/(2*n+1)! CROSSREFS Bisection of A001813. Sequence in context: A077540 A272180 A187880 * A100043 A181760 A290247 Adjacent sequences:  A024340 A024341 A024342 * A024344 A024345 A024346 KEYWORD sign AUTHOR EXTENSIONS Extended with signs by Olivier Gérard, Mar 15 1997 Edited by Ralf Stephan, Mar 25 2004 Name edited by Michel Marcus, Jul 01 2019 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 14:23 EDT 2019. Contains 328113 sequences. (Running on oeis4.)