Numbers k such that k divides 18^k - 1.

Terms

a(0) =1a(1) =17a(2) =289a(3) =4913a(4) =83521a(5) =1419857a(6) =5846759a(7) =24054337a(8) =24137569a(9) =99394903a(10) =408923729a(11) =410338673a(12) =1689713351a(13) =6951703393a(14) =6975757441a(15) =28725126967a(16) =118178957681a(17) =118285781329a(18) =118587876497a(19) =486643291847a(20) =488327158439