Numbers k such that k | 7^k + 1.

Terms

a(0) =1a(1) =2a(2) =10a(3) =50a(4) =250a(5) =1250a(6) =2810a(7) =5050a(8) =6250a(9) =14050a(10) =25250a(11) =31250a(12) =40210a(13) =70250a(14) =126250a(15) =156250a(16) =201050a(17) =351250a(18) =510050a(19) =631250a(20) =650050a(21) =781250a(22) =789610a(23) =1005250a(24) =1265050a(25) =1419050a(26) =1756250a(27) =2550250a(28) =3156250a(29) =3250250