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A009802
Expansion of tanh(sinh(log(1+x))).
0
0, 1, -1, 1, 0, -14, 150, -1322, 10976, -87824, 655920, -3981152, 5308512, 458307760, -12593915152, 254156155888, -4589735470080, 77850265751296, -1250201506099968, 18653867368039168, -241973220007075840
OFFSET
0,6
MATHEMATICA
Tanh[ Sinh[ Log[ 1+x ] ] ]
CROSSREFS
Sequence in context: A222614 A019521 A009614 * A153598 A180347 A262183
KEYWORD
sign,easy
AUTHOR
EXTENSIONS
Extended with signs by Olivier Gérard, Mar 15 1997
STATUS
approved