Primes that are concatenations of k-th composite and k-th prime.

Terms

a(0) =97a(1) =1213a(2) =2137a(3) =2861a(4) =3067a(5) =3271a(6) =3373a(7) =3583a(8) =48131a(9) =55163a(10) =56167a(11) =57173a(12) =62191a(13) =70229a(14) =86293a(15) =90313a(16) =93337a(17) =96353a(18) =99367a(19) =104383a(20) =105389a(21) =106397a(22) =108401a(23) =117443a(24) =123479a(25) =126499a(26) =129509a(27) =132523a(28) =133541a(29) =138569