A044418 - OEIS

%I #10 Jan 04 2020 19:18:47

%S 86,186,286,386,486,586,686,786,860,886,986,1086,1186,1286,1386,1486,

%T 1586,1686,1786,1860,1886,1986,2086,2186,2286,2386,2486,2586,2686,

%U 2786,2860,2886,2986,3086,3186,3286,3386,3486,3586

%N Numbers n such that string 8,6 occurs in the base 10 representation of n but not of n-1.

%t Select[Range[4000],MemberQ[Partition[IntegerDigits[#],2,1],{8,6}]&& !MemberQ[Partition[IntegerDigits[#-1],2,1],{8,6}]&] (* _Harvey P. Dale_, Oct 02 2011 *)

%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n],{8,6}]>0,1,0],{n,4000}],{0,1}][[All,2]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jan 04 2020 *)

%K nonn,base

%O 1,1

%A _Clark Kimberling_