login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

Thanks to everyone who made a donation during our annual appeal!
To see the list of donors, or make a donation, see the OEIS Foundation home page.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A009680 E.g.f. tan(sinh(x))*cos(x) (odd powers only). 0

%I

%S 1,0,12,336,15760,1144704,117385920,16206548736,2897776619776,

%T 651455951990784,179856295521635328,59822762558026321920,

%U 23594335379577078059008,10887666560228980302446592

%N E.g.f. tan(sinh(x))*cos(x) (odd powers only).

%F a(n) ~ (2*n-1)! * 4 * cos(arcsinh(Pi/2)) / (sqrt(4 + Pi^2) * arcsinh(Pi/2)^(2*n)). - _Vaclav Kotesovec_, Jan 24 2015

%t With[{nn=30},Take[CoefficientList[Series[Tan[Sinh[x]]*Cos[x],{x,0,nn}], x]Range[0,nn-1]!,{2,-1,2}]] (* _Harvey P. Dale_, Apr 01 2012 *)

%K nonn

%O 1,3

%A _R. H. Hardin_

%E Extended and signs tested Mar 15 1997 by _Olivier GĂ©rard_.

%E Changed offset by _Vaclav Kotesovec_, Jan 24 2015

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.

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 18 19:30 EST 2020. Contains 331029 sequences. (Running on oeis4.)