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%I #11 Jun 23 2015 21:37:20
%S 0,1,-1,-3,14,-15,-136,1197,-5776,-255,420224,-5448003,30166784,
%T 241437105,-8354415616,104019879597,-291139373056,-17849464279935,
%U 456381834297344,-5108933510880003,-26967886768439296,2525823613297136625
%N Expansion of log(1+tanh(x)/cosh(x)).
%t Log[ 1+Tanh[ x ]/Cosh[ x ] ]
%K sign,easy
%O 0,4
%A _R. H. Hardin_
%E Extended with signs by _Olivier Gérard_, Mar 15 1997