Semiprimes in A056109.

Terms

a(0) =6a(1) =34a(2) =57a(3) =86a(4) =121a(5) =209a(6) =262a(7) =321a(8) =386a(9) =706a(10) =1241a(11) =1366a(12) =1497a(13) =2582a(14) =2761a(15) =3334a(16) =3746a(17) =3961a(18) =4881a(19) =5377a(20) =6166a(21) =6722a(22) =7009a(23) =7601a(24) =8857a(25) =9862a(26) =10562a(27) =10921a(28) =12417a(29) =13201