Primes consisting only of digits 1 and 6 occurring with equal frequency.

Terms

a(0) =61a(1) =16166611a(2) =16616161a(3) =61116661a(4) =61661161a(5) =66161611a(6) =1166116661a(7) =1166166161a(8) =1166166611a(9) =1166616161a(10) =1616616611a(11) =1661116661a(12) =6111166661a(13) =6111666611a(14) =6116116661a(15) =6161161661a(16) =6161166161a(17) =6161166611a(18) =6161661161a(19) =6166111661a(20) =6166161161a(21) =6611616611a(22) =6616161161a(23) =6616161611