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%I #13 Jun 22 2019 11:35:36
%S 0,0,1,-3,11,-50,154,756,-25572,434736,-6324264,84312360,-1014504360,
%T 9750096720,-26179417200,-2263442045760,92224441646400,
%U -2623899775526400,64132749053646720,-1393649719639125120,25953090802663939200,-339671851067737440000
%N Expansion of e.g.f: tanh(log(1+x)^2)/2.
%t With[{nn=30},CoefficientList[Series[Tanh[Log[1+x]^2]/2,{x,0,nn}],x] Range[0,nn]!] (* _Harvey P. Dale_, Jun 22 2019 *)
%Y Cf. A009789.
%K sign
%O 0,4
%A _R. H. Hardin_
%E Extended with signs, Mar 1997
%E Definition clarified and prior Mathematica program replaced by ~~~