Positions of even numbers in A003325.

Terms

a(0) =1a(1) =3a(2) =4a(3) =6a(4) =8a(5) =10a(6) =11a(7) =13a(8) =16a(9) =18a(10) =19a(11) =21a(12) =23a(13) =25a(14) =26a(15) =28a(16) =31a(17) =33a(18) =34a(19) =35a(20) =37a(21) =39a(22) =43a(23) =44a(24) =46a(25) =47a(26) =49a(27) =51a(28) =54a(29) =56