224061282907domain: NAppears in sequencesE.g.f. 1/(2-cosh(x)) (even coefficients).at n=8A094088a(n) is the number of chains from {} to a top element in the poset of even sized subsets of {1,2,...,n} ordered by inclusion.at n=16A336012E.g.f.: (exp(-x) - exp(x) - 2)/(exp(-x) + exp(x) - 4).at n=16A375381