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A024249 revision #3

A024249

Expansion of tanh(tan(x)).tan(x)/2.

0, 1, 4, 24, 192, 9472, 1182208, 135668736, 14993473536, 1702145425408, 212302947942400, 32402586267549696, 6715751146400514048, 1845064263947813650432, 597912413872386432040960

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,3

LINKS

Table of n, a(n) for n=0..14.

MATHEMATICA

Tanh[ Tan[ x ] ]*Tan[ x ]/2 (* Even Part *)

CROSSREFS

A009812.

Sequence in context: A182798 A374852 A073840 * A007145 A241000 A305988

Adjacent sequences: A024246 A024247 A024248 * A024250 A024251 A024252

KEYWORD

nonn,new

AUTHOR

R. H. Hardin (rhh(AT)cadence.com)

EXTENSIONS

Extended and signs tested 03/97.

STATUS

approved