Least k such that base 6 representation of n begins at s(k), where s=A030586.

Terms

a(0) =4a(1) =3a(2) =2a(3) =1a(4) =7a(5) =4a(6) =50a(7) =39a(8) =27a(9) =15a(10) =42a(11) =40a(12) =3a(13) =36a(14) =25a(15) =13a(16) =30a(17) =28a(18) =26a(19) =2a(20) =22a(21) =11a(22) =18a(23) =16a(24) =14a(25) =12a(26) =1a(27) =8a(28) =6a(29) =55