a(n)=least k such that the base 6 representation of n begins at s(k), where s=A030604.

Terms

a(0) =1a(1) =2a(2) =3a(3) =12a(4) =4a(5) =22a(6) =38a(7) =1a(8) =8a(9) =26a(10) =43a(11) =50a(12) =7a(13) =6a(14) =2a(15) =30a(16) =17a(17) =237a(18) =14a(19) =35a(20) =9a(21) =70a(22) =3a(23) =19a(24) =12a(25) =27a(26) =34a(27) =33a(28) =31a(29) =112