-7744domain: ZAppears in sequencessech(tanh(x)+arctan(x))=1-4/2!*x^2+112/4!*x^4-7744/6!*x^6...at n=3A013151Coefficients in the expansion of 1/([r] + [2r]x + [3r]x^2 + ...); [ ] = floor, r = 9/5.at n=29A279781