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%I #9 Dec 04 2019 13:56:11
%S 22,47,72,97,110,122,147,172,197,222,235,247,272,297,322,347,360,372,
%T 397,422,447,472,485,497,522,547,550,597,610,622,647,672,697,722,735,
%U 747,772,797,822,847,860,872,897,922,947,972
%N Numbers n such that string 4,2 occurs in the base 5 representation of n but not of n-1.
%H Harvey P. Dale, <a href="/A044099/b044099.txt">Table of n, a(n) for n = 1..1000</a>
%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n,5],{4,2}]>0,1,0],{n,1000}],{0,1}][[All,2]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Dec 04 2019 *)
%K nonn,base
%O 1,1
%A _Clark Kimberling_