Position of n-th 6 in A031100.

Terms

a(0) =12a(1) =30a(2) =48a(3) =51a(4) =53a(5) =55a(6) =57a(7) =66a(8) =88a(9) =115a(10) =142a(11) =159a(12) =162a(13) =165a(14) =168a(15) =169a(16) =171a(17) =196a(18) =223a(19) =250a(20) =277a(21) =282a(22) =285a(23) =288a(24) =291a(25) =304a(26) =331a(27) =358a(28) =385a(29) =402