Numbers k such that (89*10^k - 179)/9 is prime.

Terms

a(0) =1a(1) =4a(2) =10a(3) =12a(4) =15a(5) =52a(6) =72a(7) =150a(8) =160a(9) =271a(10) =732a(11) =1566a(12) =2673a(13) =4840a(14) =7818a(15) =9016a(16) =9441a(17) =9448a(18) =11190a(19) =15792a(20) =64504a(21) =80650a(22) =115030a(23) =140008