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%I #13 Aug 25 2021 04:53:22
%S 5,30,51,55,76,80,101,105,155,176,180,201,205,226,230,251,259,280,301,
%T 305,326,330,351,355,376,384,405,426,430,451,455,476,480,501,509,530,
%U 551,555,576,580,601,605,780,801,805,826,830
%N Numbers k such that 0 and 1 occur juxtaposed in the base-5 representation of k but not of k+1.
%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n,5],{0,1}]>0 || SequenceCount[IntegerDigits[n,5],{1,0}]>0,1,0],{n,900}],{1,0}][[All,1]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jun 14 2017 *)
%Y Cf. A007091.
%K nonn,base
%O 1,1
%A _Clark Kimberling_