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A009391 Expansion of ln(1+tanh(x))/cos(x). 2
0, 1, -1, 3, -4, 25, -61, 427, -1184, 12465, -49201, 555731, -2361844, 35135945, -191422141, 2990414715, -17147588384, 329655706465, -2289437638081, 45692713833379, -329955144475204, 7777794952988025, -65643617893832221 (list; graph; refs; listen; history; internal format)
OFFSET

0,4

MATHEMATICA

Log[ 1+Tanh[ x ] ]/Cos[ x ]

CROSSREFS

a(2n+1) = A009843(n), |a(2n)| = A009391(2n).

Sequence in context: A065809 A093600 A128778 * A192346 A055348 A004206

Adjacent sequences:  A009388 A009389 A009390 * A009392 A009393 A009394

KEYWORD

sign,easy

AUTHOR

R. H. Hardin (rhhardin(AT)att.net)

EXTENSIONS

Extended with signs Mar 15 1997 by Olivier Gerard.

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Last modified February 15 03:59 EST 2012. Contains 205694 sequences.