a(n) = least positive integer > a(n-1) and not a(i)*a(j)+2 for 1<=i<j<=n, with initial terms 3,4.

Terms

a(0) =3a(1) =4a(2) =5a(3) =6a(4) =7a(5) =8a(6) =9a(7) =10a(8) =11a(9) =12a(10) =13a(11) =15a(12) =16a(13) =18a(14) =19a(15) =21a(16) =24a(17) =25a(18) =27a(19) =28a(20) =31a(21) =33a(22) =36a(23) =39a(24) =40a(25) =43a(26) =45a(27) =48a(28) =49a(29) =51