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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A013334 Expansion of e.g.f. arcsinh(exp(x) - sec(x)). 1

%I

%S 0,1,0,0,-4,0,0,0,-1104,-5040,0,184800,-1784704,-39948480,-201801600,

%T 2969366400,24788541696,-621491320320,-12903078988800,20131497484800,

%U 2944178363780096,8434762785469440,-1051002016730265600,-14118259471683840000,255660771276061802496

%N Expansion of e.g.f. arcsinh(exp(x) - sec(x)).

%H Vincenzo Librandi, <a href="/A013334/b013334.txt">Table of n, a(n) for n = 0..200</a>

%e x - 4/4!*x^4 - 1104/8!*x^8 - 5040/9!*x^9 ...

%t Range[0, 30]! CoefficientList[Series[ArcSinh[Exp[x] - Sec[x]], {x, 0, 30}], x] (* _Vincenzo Librandi_, Aug 06 2018 *)

%o (MAGMA) m:=30; R<x>:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!(1+Argsinh(Exp(x) - Sec(x)))); [0] cat [Factorial(n-1)*b[n]: n in [2..m]]; // _Vincenzo Librandi_, Aug 06 2018

%o (PARI) x = 'x + O('x^30); concat(0, Vec(serlaplace(asinh(exp(x) - 1/cos(x))))) \\ _Michel Marcus_, Aug 06 2018

%K sign

%O 0,5

%A Patrick Demichel (patrick.demichel(AT)hp.com)

%E a(0)=0 inserted and title improved by _Sean A. Irvine_, Aug 05 2018

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 October 17 07:39 EDT 2021. Contains 348048 sequences. (Running on oeis4.)