Composite k that divides 2^(k-2) + 3^(k-2) + 6^(k-2) - 1.

Terms

a(0) =4a(1) =6a(2) =8a(3) =12a(4) =24a(5) =25a(6) =125a(7) =174a(8) =228a(9) =276a(10) =325a(11) =348a(12) =451a(13) =1032a(14) =1105a(15) =1128a(16) =1729a(17) =2388a(18) =2465a(19) =2701a(20) =2821a(21) =3721a(22) =5272a(23) =5365a(24) =6601a(25) =8911a(26) =10585a(27) =12025a(28) =12673a(29) =15841