Numbers k such that (26*10^k - 89) / 9 is prime.

Terms

a(0) =1a(1) =3a(2) =4a(3) =13a(4) =15a(5) =21a(6) =27a(7) =63a(8) =70a(9) =123a(10) =136a(11) =178a(12) =208a(13) =265a(14) =411a(15) =457a(16) =856a(17) =2401a(18) =4642a(19) =8017a(20) =8211a(21) =8385a(22) =12337a(23) =20793a(24) =123970a(25) =189928