%I #10 Aug 27 2021 07:07:36
%S 10,110,201,210,301,310,401,410,501,510,601,610,701,710,801,810,901,
%T 910,1110,1201,1210,1301,1310,1401,1410,1501,1510,1601,1610,1701,1710,
%U 1801,1810,1901,1910,2001,2019,2110,2201,2210,2301
%N Numbers k such that 0 and 1 occur juxtaposed in the base-10 representation of k but not of k+1.
%t Transpose[SequencePosition[Table[If[SequenceCount[IntegerDigits[n],{0,1}]>0||SequenceCount[IntegerDigits[n],{1,0}]>0,1,0],{n,2500}],{1,0}]][[1]] (* The program uses the SequencePosition and SequenceCount functions from Mathematica version 10 *) (* _Harvey P. Dale_, Jan 10 2016 *)
%K nonn,base
%O 1,1
%A _Clark Kimberling_