Numbers k that divide 8^k - 1.

Terms

a(0) =1a(1) =7a(2) =49a(3) =343a(4) =889a(5) =2359a(6) =2401a(7) =6223a(8) =16513a(9) =16807a(10) =43561a(11) =112903a(12) =115591a(13) =117649a(14) =299593a(15) =304927a(16) =790321a(17) =794983a(18) =809137a(19) =823543a(20) =2033143a(21) =2097151a(22) =2134489a(23) =5532247a(24) =5564881a(25) =5663959a(26) =5764801a(27) =13549249a(28) =14232001a(29) =14338681