Interleave A007583 and A000012.

Terms

a(0) =1a(1) =1a(2) =3a(3) =1a(4) =11a(5) =1a(6) =43a(7) =1a(8) =171a(9) =1a(10) =683a(11) =1a(12) =2731a(13) =1a(14) =10923a(15) =1a(16) =43691a(17) =1a(18) =174763a(19) =1a(20) =699051a(21) =1a(22) =2796203a(23) =1a(24) =11184811a(25) =1a(26) =44739243a(27) =1a(28) =178956971a(29) =1