Numbers k such that 11^k == -1 (mod k-1).

Terms

a(0) =2a(1) =3a(2) =5a(3) =7a(4) =13a(5) =62a(6) =75a(7) =378a(8) =637a(9) =2295a(10) =10933a(11) =24255a(12) =31125a(13) =50787a(14) =53685a(15) =55575a(16) =176565a(17) =193242a(18) =243165a(19) =290675a(20) =415215a(21) =579397a(22) =728035a(23) =728742a(24) =741015a(25) =760410a(26) =1281423a(27) =1447515a(28) =1664205a(29) =1975974