%I #7 May 10 2019 15:36:53

%S 41,141,241,341,419,441,541,641,741,841,941,1041,1141,1241,1341,1419,

%T 1441,1541,1641,1741,1841,1941,2041,2141,2241,2341,2419,2441,2541,

%U 2641,2741,2841,2941,3041,3141,3241,3341,3419,3441

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

%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n],{4,1}]>0,1,0],{n,3500}],{1,0}][[All,1]] (* _Harvey P. Dale_, May 10 2019 *)

%K nonn,base

%O 1,1

%A _Clark Kimberling_