-9968domain: ZAppears in sequencesExpansion of e.g.f. sech(arcsinh(x)*arctan(x)) (only even powers).at n=4A012633cos(arctanh(x)*arctan(x)) = 1-12/4!*x^4-9968/8!*x^8-77575872/12!*x^12...at n=2A012732Expansion of g.f. (1-x+x^2)/(1+x-x^3).at n=60A104771a(n) = Sum_{k=0..n} binomial(n,k)^3 * k! * (-2)^(n-k).at n=6A354941