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A024228 Expansion of tanh(x)*tan(sin(x))/2. 0
0, 1, -2, 19, -900, 24677, -1112326, 106703735, -9757606664, 1107210680265, -185352374028298, 34591783336998875, -7446994657977107084, 2008734448727225846317, -618914330538196467929358 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

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

MATHEMATICA

With[{nn=40}, Take[CoefficientList[Series[Tanh[x]*Tan[Sin[x]]/2, {x, 0, nn}], x]Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Apr 27 2012 *)

CROSSREFS

Cf. A009835.

Sequence in context: A012980 A323280 A013110 * A015191 A165937 A128345

Adjacent sequences:  A024225 A024226 A024227 * A024229 A024230 A024231

KEYWORD

sign

AUTHOR

R. H. Hardin

EXTENSIONS

Extended with signs Mar 1997

STATUS

approved

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Last modified October 27 23:26 EDT 2020. Contains 338047 sequences. (Running on oeis4.)