A044758 - OEIS

%I #7 May 09 2018 12:16:05

%S 45,145,245,345,445,459,545,645,745,845,945,1045,1145,1245,1345,1445,

%T 1459,1545,1645,1745,1845,1945,2045,2145,2245,2345,2445,2459,2545,

%U 2645,2745,2845,2945,3045,3145,3245,3345,3445,3459

%N Numbers n such that string 4,5 occurs in the base 10 representation of n but not of n+1.

%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n],{4,5}]>0,1,0],{n,3500}],{1,0}][[All,1]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, May 09 2018 *)

%K nonn,base

%O 1,1

%A _Clark Kimberling_