Numbers k such that 18*10^k + 1 is prime.

Terms

a(0) =0a(1) =1a(2) =2a(3) =4a(4) =9a(5) =12a(6) =21a(7) =55a(8) =307a(9) =332a(10) =388a(11) =820a(12) =1593a(13) =2432a(14) =2438a(15) =3372a(16) =6270a(17) =7437a(18) =8268a(19) =12135a(20) =16588a(21) =41397a(22) =46126a(23) =47910a(24) =81091