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A013237
Expansion of e.g.f. arctan(log(x+1) - tan(x)).
1
0, 0, -1, 0, -6, 8, -90, 448, -2520, 26336, -120960, 1722688, -8914752, 110138624, -763819056, 2510508544, -23764540800, -1852444415488, 25138910788992, -839278029937664, 14518492774196480, -301837255570263040, 6080193763585041408, -100072615179212095488
OFFSET
0,5
LINKS
EXAMPLE
-1/2!*x^2 - 6/4!*x^4 + 8/5!*x^5 - 90/6!*x^6 ...
MATHEMATICA
Range[0, 25]! CoefficientList[Series[ArcTan[Log[x + 1] - Tan[x]], {x, 0, 25}], x] (* Vincenzo Librandi, Aug 02 2018 *)
PROG
(PARI) x = 'x + O('x^30); concat([0, 0], Vec(serlaplace(atan(log(x+1) - tan(x))))) \\ Michel Marcus, Aug 02 2018
CROSSREFS
Sequence in context: A216796 A137127 A013241 * A013234 A013240 A161801
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
EXTENSIONS
a(0)=a(1)=0 inserted and title improved by Sean A. Irvine, Aug 02 2018
STATUS
approved