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%I #11 Mar 19 2018 11:44:31
%S 25,61,97,133,155,169,205,241,277,313,349,371,385,421,457,493,529,565,
%T 587,601,637,673,709,745,781,803,817,853,889,935,961,997,1019,1033,
%U 1069,1105,1141,1177,1213,1235,1249,1285,1321,1357,1393,1429,1451,1465,1501
%N Numbers n such that string 4,1 occurs in the base 6 representation of n but not of n+1.
%t f[n_] := Length[StringPosition[ToString[FromDigits[IntegerDigits[n, 6]]], "41", 1]]; Select[Table[n, {n, 10000}], f[#] > 0 && f[# + 1] == 0 &] (* _Vladimir Joseph Stephan Orlovsky_, Jul 20 2011 *)
%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n,6],{4,1}]>0,1,0],{n,1600}],{1,0}][[All,1]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Mar 19 2018 *)
%Y Cf. A044127.
%K nonn,base
%O 1,1
%A _Clark Kimberling_
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