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%I #11 Jan 15 2024 19:02:31
%S 0,1,-2,63,-1684,47885,-2204406,132744619,-9077359208,742552576857,
%T -73321393543210,8347807403373911,-1073637784611054972,
%U 156252386332716624613,-25582992239831815086494
%N Expansion of sinh(sin(x)*x)/2.
%t With[{nn=30},Take[CoefficientList[Series[Sinh[Sin[x]x]/2,{x,0,nn}],x] Range[0,nn]!,{1,-1,2}]] (* _Harvey P. Dale_, Jan 15 2024 *)
%Y Cf. A009595.
%K sign
%O 0,3
%A _R. H. Hardin_
%E Extended with signs Mar 1997
%E Previous Mathematica program replaced by _Harvey P. Dale_, Jan 15 2024