OFFSET
0,3
FORMULA
E.g.f. of aerated sequence: Sum(n>=0, a(n)*x^(2*n)/(2*n)!) = log(1+tan(x)*x)/2. - Robert Israel, Jun 29 2015
MAPLE
S:= series(log(1+tan(x)*x)/2, x, 101): seq(coeff(S, x, 2*j)*(2*j)!, j=0..50); # Robert Israel, Jun 29 2015
MATHEMATICA
With[{nn=30}, Take[CoefficientList[Series[Log[1+Tan[x]x]/2, {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Jun 24 2018 *)
CROSSREFS
KEYWORD
sign
AUTHOR
EXTENSIONS
Extended with signs, Mar 1997
Previous Mathematica program replaced by Harvey P. Dale, Jun 24 2018
STATUS
approved