A043233 - OEIS

%I #10 Aug 23 2021 21:45:47

%S 23,32,123,132,223,230,320,332,423,432,523,532,623,632,723,732,823,

%T 832,923,932,1023,1032,1123,1132,1223,1230,1320,1332,1423,1432,1523,

%U 1532,1623,1632,1723,1732,1823,1832,1923,1932,2023

%N Numbers k such that 2 and 3 occur juxtaposed in the base-10 representation of k but not of k-1.

%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n],{2,3}]>0 || SequenceCount[ IntegerDigits[n],{3,2}]>0,1,0],{n,2100}],{0,1}][[All,2]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Oct 31 2020 *)

%K nonn,base

%O 1,1

%A _Clark Kimberling_