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A009401
Expansion of log(1+tanh(x)/cosh(x)).
0
0, 1, -1, -3, 14, -15, -136, 1197, -5776, -255, 420224, -5448003, 30166784, 241437105, -8354415616, 104019879597, -291139373056, -17849464279935, 456381834297344, -5108933510880003, -26967886768439296, 2525823613297136625
OFFSET
0,4
MATHEMATICA
Log[ 1+Tanh[ x ]/Cosh[ x ] ]
CROSSREFS
Sequence in context: A303222 A037244 A016062 * A195864 A349767 A022890
KEYWORD
sign,easy
AUTHOR
EXTENSIONS
Extended with signs by Olivier Gérard, Mar 15 1997
STATUS
approved