-11263domain: ZAppears in sequencescos(sec(x)*arcsin(x))=1-1/2!*x^2-15/4!*x^4-345/6!*x^6-11263/8!*x^8...at n=4A012787Expansion of e.g.f.: exp(sech(x)*arcsinh(x))=1+x+1/2!*x^2-3/3!*x^3-15/4!*x^4+5/5!*x^5...at n=8A012881a(n) = Sum_{d|n} mu(n/d) * d * (n/d)^(d-1), where mu() is the Moebius function (A008683).at n=21A359188