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%I #7 Jul 03 2020 18:57:11
%S 30,66,102,138,174,180,210,246,282,318,354,390,396,426,462,498,534,
%T 570,606,612,642,678,714,750,786,822,828,858,894,930,966,1002,1038,
%U 1044,1074,1080,1146,1182,1218,1254,1260,1290,1326
%N Numbers n such that string 5,0 occurs in the base 6 representation of n but not of n-1.
%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n,6],{5,0}]>0,1,0],{n,1400}],{0,1}][[All,2]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jul 03 2020 *)
%K nonn,base
%O 1,1
%A _Clark Kimberling_