Position of n-th 6 in A031067.

Terms

a(0) =13a(1) =63a(2) =66a(3) =84a(4) =97a(5) =104a(6) =124a(7) =138a(8) =148a(9) =157a(10) =158a(11) =179a(12) =187a(13) =189a(14) =198a(15) =202a(16) =209a(17) =212a(18) =218a(19) =223a(20) =228a(21) =244a(22) =253a(23) =259a(24) =262a(25) =271a(26) =294a(27) =297a(28) =307a(29) =308