E.g.f.: exp(x^2 * exp(-x)).

Terms

a(0) =1a(1) =0a(2) =2a(3) =-6a(4) =24a(5) =-140a(6) =870a(7) =-5922a(8) =45416a(9) =-381096a(10) =3442410a(11) =-33382910a(12) =345803172a(13) =-3801763836a(14) =44156760830a(15) =-539962736250