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

Terms

a(0) =1a(1) =2a(2) =9a(3) =61a(4) =551a(5) =6221a(6) =84285a(7) =1332255a(8) =24066691a(9) =489100297a(10) =11044268633a(11) =274327080611