Numbers k that divide 7^k + 4^k.

Terms

a(0) =1a(1) =11a(2) =121a(3) =253a(4) =737a(5) =1331a(6) =2783a(7) =5819a(8) =8107a(9) =14641a(10) =16951a(11) =30613a(12) =49379a(13) =64009a(14) =89177a(15) =116897a(16) =133837a(17) =161051a(18) =186461a(19) =336743a(20) =389873a(21) =543169a(22) =640343a(23) =704099a(24) =980947a(25) =1135717a(26) =1285867a(27) =1292071a(28) =1472207a(29) =1771561