Expansion of e.g.f. 1/(exp(x) - x^2/2).

Terms

a(0) =1a(1) =-1a(2) =2a(3) =-7a(4) =31a(5) =-171a(6) =1141a(7) =-8863a(8) =78653a(9) =-785557a(10) =8716861a(11) =-106395741a(12) =1416724915a(13) =-20436548575a(14) =317477947151