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

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A003722 E.g.f. sin(sinh(x)) (odd powers only).
(Formerly M4541)
4

%I M4541 #21 Apr 11 2014 05:09:44

%S 1,0,-8,-56,64,12672,309376,2917888,-163782656,-12716052480,

%T -495644917760,-4004259037184,1359174582304768,153146435763437568,

%U 9620207941273255936,142966118908253962240,-62984506636368191946752

%N E.g.f. sin(sinh(x)) (odd powers only).

%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

%H Vincenzo Librandi, <a href="/A003722/b003722.txt">Table of n, a(n) for n = 0..100</a>

%F a(n) = sum(j=1..n+1, (sum(i=0..2*j-1, (-1)^(i+j-1)*(2*j-1-2*i)^(2*n+1)*binomial(2*j-1,i)))/(2^(2*j-1)*(2*j-1)!)); [_Vladimir Kruchinin_, Jun 09 2011]

%t With[{nn = 50}, Take[CoefficientList[Series[Sin[Sinh[x]], {x, 0, nn}], x] Range[0, nn - 1]!, {2, -1, 2}]] (* _Vincenzo Librandi_, Apr 11 2014 *)

%o (Maxima)

%o a(n):=sum((sum((-1)^(i+j-1)*(2*j-1-2*i)^(2*n+1)*binomial(2*j-1,i),i,0,2*j-1))/(2^(2*j-1)*(2*j-1)!),j,1,n+1); /* _Vladimir Kruchinin_, Jun 09 2011 */

%K sign

%O 0,3

%A _R. H. Hardin_, _Simon Plouffe_

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.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 24 14:17 EDT 2024. Contains 371960 sequences. (Running on oeis4.)