Position of n-th 6 in A031007.

Terms

a(0) =6a(1) =19a(2) =33a(3) =47a(4) =61a(5) =75a(6) =78a(7) =80a(8) =82a(9) =84a(10) =86a(11) =88a(12) =89a(13) =90a(14) =109a(15) =130a(16) =151a(17) =172a(18) =193a(19) =214a(20) =218a(21) =221a(22) =224a(23) =227a(24) =230a(25) =233a(26) =235a(27) =236a(28) =256a(29) =277