43589145601domain: NAppears in sequencesa(n) = (n!+2)/2.at n=12A139149From the coefficients (times n!) of the expansion of the Sum_{k>=1} cos(x^k).at n=7A176474a(n) = 7*n! + 1.at n=13A229554Expansion of e.g.f. Sum_{k>=1} (cosh(x^k) - 1) (even powers only).at n=6A330255