The OEIS is supported by the many generous donors to the OEIS Foundation.
%I #7 Jan 02 2020 12:58:31
%S 27,63,99,135,162,171,207,243,279,315,351,378,387,423,459,495,531,567,
%T 594,603,639,675,711,747,783,810,819,855,891,927,963,972,1026,1035,
%U 1071,1107,1143,1179,1215,1242,1251,1287,1323,1359
%N Numbers n such that string 4,3 occurs in the base 6 representation of n but not of n-1.
%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n,6],{4,3}]>0,1,0],{n,1500}],{0,1}][[All,2]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jan 02 2020 *)
%K nonn,base
%O 1,1
%A _Clark Kimberling_