%I #7 Nov 28 2015 13:47:53

%S 43,143,243,343,439,443,543,643,743,843,943,1043,1143,1243,1343,1439,

%T 1443,1543,1643,1743,1843,1943,2043,2143,2243,2343,2439,2443,2543,

%U 2643,2743,2843,2943,3043,3143,3243,3343,3439,3443

%N Numbers n such that string 4,3 occurs in the base 10 representation of n but not of n+1.

%t Transpose[SequencePosition[Table[If[SequenceCount[IntegerDigits[n],{4,3}]>0,1,0],{n,3500}],{1,0}]][[1]] (* The program uses the SequencePosition and SequenceCount functions from Mathematica version 10 *) (* _Harvey P. Dale_, Nov 28 2015 *)

%K nonn,base

%O 1,1

%A _Clark Kimberling_