Expansion of e.g.f. exp(x/(1 + 2*x)).

Terms

a(0) =1a(1) =1a(2) =-3a(3) =13a(4) =-71a(5) =441a(6) =-2699a(7) =9157a(8) =206193a(9) =-8443151a(10) =236126701a(11) =-6169406979a(12) =161388751657