a(n) = numerator of A000032(n) - 1/2^n.

Terms

a(0) =1a(1) =1a(2) =11a(3) =31a(4) =111a(5) =351a(6) =1151a(7) =3711a(8) =12031a(9) =38911a(10) =125951a(11) =407551a(12) =1318911a(13) =4268031a(14) =13811711a(15) =44695551a(16) =144637951a(17) =468058111a(18) =1514668031a(19) =4901568511a(20) =15861809151a(21) =51329892351a(22) =166107021311a(23) =537533612031