Smallest semiprimes such that a(j) - a(k) are all different.

Terms

a(0) =4a(1) =6a(2) =9a(3) =10a(4) =21a(5) =34a(6) =55a(7) =65a(8) =74a(9) =94a(10) =141a(11) =177a(12) =203a(13) =219a(14) =298a(15) =321a(16) =395a(17) =403a(18) =529a(19) =581a(20) =635a(21) =662a(22) =731a(23) =934a(24) =982a(25) =1073a(26) =1145a(27) =1317a(28) =1418a(29) =1762