Where the prime race among 7k+1, ..., 7k+6 changes leader.

Terms

a(0) =2a(1) =17a(2) =131a(3) =227a(4) =733a(5) =829a(6) =929a(7) =997a(8) =1097a(9) =1123a(10) =1237a(11) =1277a(12) =1447a(13) =1487a(14) =1531a(15) =1627a(16) =1811a(17) =1907a(18) =1993a(19) =2141a(20) =2203a(21) =2267a(22) =2441a(23) =2677a(24) =2707a(25) =3209a(26) =3299a(27) =3433a(28) =3547a(29) =3853