OFFSET
0,2
FORMULA
a(n) ~ c * (2*n)! / sqrt(n), where c = 1/(sqrt(Pi) * (sin(sin(1)))^2) = 1.0148109425617531683... . - Vaclav Kotesovec, Feb 29 2016
MATHEMATICA
nn = 20; Table[(CoefficientList[Series[Cot[ArcCos[x] + Sin[x]], {x, 0, 2*nn+1}], x] * Range[0, 2*nn+1]!)[[n]], {n, 2, 2*nn, 2}] (* Vaclav Kotesovec, Feb 06 2015 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
EXTENSIONS
a(0)=0 prepended by Vaclav Kotesovec, Feb 06 2015
Definition modified by Vaclav Kotesovec, Feb 06 2015
STATUS
approved