Semiprimes (or biprimes): products of two primes.

Terms

a(0) =4a(1) =6a(2) =9a(3) =10a(4) =14a(5) =15a(6) =21a(7) =22a(8) =25a(9) =26a(10) =33a(11) =34a(12) =35a(13) =38a(14) =39a(15) =46a(16) =49a(17) =51a(18) =55a(19) =57a(20) =58a(21) =62a(22) =65a(23) =69a(24) =74a(25) =77a(26) =82a(27) =85a(28) =86a(29) =87