E.g.f.: exp( exp(x + x^2/2) - 1 ).

Terms

a(0) =1a(1) =1a(2) =3a(3) =11a(4) =51a(5) =277a(6) =1733a(7) =12175a(8) =94741a(9) =806613a(10) =7446655a(11) =73987135a(12) =786304687a(13) =8892165193a(14) =106533442265