%I #9 Mar 30 2022 18:37:02
%S 20,84,148,160,212,276,340,404,468,532,596,660,672,724,788,852,916,
%T 980,1044,1108,1172,1184,1236,1280,1364,1428,1492,1556,1620,1684,1696,
%U 1748,1812,1876,1940,2004,2068,2132,2196,2208,2260
%N Numbers n such that string 2,4 occurs in the base 8 representation of n but not of n-1.
%H Harvey P. Dale, <a href="/A044207/b044207.txt">Table of n, a(n) for n = 1..1000</a>
%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n,8],{2,4}]>0,1,0],{n,2500}],{0,1}][[All,2]] (* _Harvey P. Dale_, Mar 30 2022 *)
%K nonn,base
%O 1,1
%A _Clark Kimberling_