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!)
A009433 Expansion of log(1+x)/cosh(tan(x)). 0

%I #13 Jun 23 2015 21:44:14

%S 0,1,-1,-1,0,-11,15,27,-504,11817,-94185,1226455,-12442056,155936221,

%T -1995562569,27870901107,-423463160400,6793396567633,-117302680146033,

%U 2130615128588591,-40960288523646320,827190717641773765

%N Expansion of log(1+x)/cosh(tan(x)).

%F a(n) ~ (n-1)! * (-1)^(n+1) / cosh(tan(1)). - _Vaclav Kotesovec_, Jan 23 2015

%t Log[ 1+x ]/Cosh[ Tan[ x ] ]

%t CoefficientList[Series[Log[1 + x]*Sech[Tan[x]], {x, 0, 20}], x] * Range[0, 20]! (* _Vaclav Kotesovec_, Jan 23 2015 *)

%K sign,easy

%O 0,6

%A _R. H. Hardin_

%E Extended with signs by _Olivier GĂ©rard_, Mar 15 1997

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 May 29 13:20 EDT 2023. Contains 363042 sequences. (Running on oeis4.)