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%I #15 Mar 10 2014 08:19:44
%S 0,0,-4,60,-1384,50520,-2333164,98460180,2691348656,-2502877578960,
%T 816953866876076,-250462447769994900,80927047278922241096,
%U -28429551522622456235640,10951929595731882160395716
%N E.g.f.: sin(cos(x)-sech(x)) (even powers only).
%H Vincenzo Librandi, <a href="/A013483/b013483.txt">Table of n, a(n) for n = 0..50</a>
%e sin(cos(x)-sech(x))=0*x^0+0*x^2-4/4!*x^4+60/6!*x^6-1384/8!*x^8+50520/10!*x^10...
%t With[{nn=30},Take[CoefficientList[Series[Sin[Cos[x]-Sech[x]],{x,0,nn}],x] Range[0,nn]!,{1,-1,2}]] (* _Harvey P. Dale_, Mar 09 2014 *)
%K sign
%O 0,3
%A Patrick Demichel (patrick.demichel(AT)hp.com)
%E Name clarified, a(0)=a(1)=1 prepended, _Joerg Arndt_, Mar 09 2014