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%I #14 Apr 02 2017 15:37:21
%S 0,1,-10,288,-16656,1629440,-242569728,51150403584,-14514466195456,
%T 5334038568566784,-2464645606175539200,1398530065161670098944,
%U -956068708752272063987712,775009022325905883458961408,-735038625130292891682693185536
%N Expansion of log(1+tanh(x)*x)/2.
%t With[{nn=30},Take[CoefficientList[Series[Log[1+Tanh[x]*x]/2,{x,0,nn}],x] Range[0,nn]!,{1,-1,2}]] (* _Harvey P. Dale_, Mar 04 2013 *)
%Y Cf. A009399.
%K sign
%O 0,3
%A _R. H. Hardin_
%E Extended with signs Mar 1997