A044720 - OEIS

%I #7 Sep 22 2016 14:14:10

%S 107,207,307,407,507,607,707,807,907,1007,1079,1107,1207,1307,1407,

%T 1507,1607,1707,1807,1907,2007,2079,2107,2207,2307,2407,2507,2607,

%U 2707,2807,2907,3007,3079,3107,3207,3307,3407,3507

%N Numbers n such that string 0,7 occurs in the base 10 representation of n but not of n+1.

%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n],{0,7}]>0,1,0],{n,4000}],{1,0}][[All,1]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Sep 22 2016 *)

%K nonn,base

%O 1,1

%A _Clark Kimberling_