a(n) is the least k with k > a(n-1) such that A000120(k) = A002487(n), with a(0) = 0.

Terms

a(0) =0a(1) =1a(2) =2a(3) =3a(4) =4a(5) =7a(6) =9a(7) =11a(8) =16a(9) =23a(10) =25a(11) =31a(12) =33a(13) =47a(14) =49a(15) =51a(16) =64a(17) =79a(18) =83a(19) =127a(20) =131a(21) =255a(22) =271a(23) =319a(24) =320a(25) =351a(26) =355a(27) =383a(28) =385a(29) =415