a(n) = least positive integer > a(n-1) and not a(j)*a(k) + a(k)*a(i) + a(i)*a(j) for 1<=i<=j<=k<=n.

Terms

a(0) =1a(1) =2a(2) =4a(3) =6a(4) =7a(5) =10a(6) =11a(7) =16a(8) =17a(9) =18a(10) =19a(11) =22a(12) =25a(13) =26a(14) =27a(15) =29a(16) =30a(17) =31a(18) =36a(19) =38a(20) =40a(21) =41a(22) =42a(23) =43a(24) =46a(25) =47a(26) =49a(27) =52a(28) =57a(29) =58