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A024241
E.g.f. tan(x)*sin(tanh(x))/2 (even powers only).
0
0, 1, -2, 99, -2020, 158437, -9588134, 1187244807, -141412522312, 26139574347337, -5065084577305802, 1323760751709283371, -375086579956164869164, 132463397392835073766957, -51304161208549419113557358
OFFSET
0,3
EXAMPLE
tan(x)*sin(tanh(x))/2 = x^2 - 2*x^4 + 99*x^6 - 2020*x^8 + 158437*x^10 -+ ...
MATHEMATICA
With[{nn=30}, Take[CoefficientList[Series[Tan[x]Sin[Tanh[x]]/2, {x, 0, nn}], x]Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Jan 12 2013 *)
CROSSREFS
Cf. A009743.
Sequence in context: A324266 A258399 A212838 * A278684 A024242 A276386
KEYWORD
sign
AUTHOR
EXTENSIONS
Extended with signs Mar 1997
STATUS
approved