Duplicate of A023759.

Terms

a(0) =1a(1) =2a(2) =3a(3) =4a(4) =6a(5) =7a(6) =8a(7) =9a(8) =12a(9) =13a(10) =18a(11) =21a(12) =22a(13) =24a(14) =25a(15) =26a(16) =27a(17) =36a(18) =39a(19) =40a(20) =54a(21) =63a(22) =66a(23) =67a(24) =72a(25) =75a(26) =76a(27) =78a(28) =79a(29) =80