Semiprimes that are the concatenation of a prime and the previous prime.

Terms

a(0) =1713a(1) =2319a(2) =2923a(3) =4341a(4) =6159a(5) =7167a(6) =8983a(7) =103101a(8) =151149a(9) =157151a(10) =163157a(11) =167163a(12) =173167a(13) =191181a(14) =197193a(15) =233229a(16) =257251a(17) =277271a(18) =283281a(19) =311307a(20) =337331a(21) =367359a(22) =373367a(23) =421419a(24) =431421a(25) =439433a(26) =449443a(27) =463461a(28) =467463a(29) =479467