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%I #10 Aug 16 2024 19:53:52
%S 40,104,140,204,240,304,340,400,440,504,540,604,640,704,740,804,840,
%T 904,940,1004,1040,1104,1140,1204,1240,1304,1340,1400,1440,1504,1540,
%U 1604,1640,1704,1740,1804,1840,1904,1940,2004,2040
%N Numbers k such that 0 and 4 occur juxtaposed in the base-10 representation of k but not of k-1.
%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n],{0,4}]>0||SequenceCount[ IntegerDigits[ n],{4,0}]>0,1,0],{n,3000}],{0,1}][[;;,2]] (* _Harvey P. Dale_, Aug 16 2024 *)
%K nonn,base
%O 1,1
%A _Clark Kimberling_