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%I #14 Aug 04 2023 17:08:05
%S 17,32,53,68,89,102,125,140,161,176,192,212,233,248,269,284,305,318,
%T 341,356,377,392,408,428,449,464,485,500,521,534,557,572,593,608,612,
%U 665,680,701,716,737,750,773,788,809,824,840,860
%N Numbers k such that 2 and 5 occur juxtaposed in the base-6 representation of k but not of k-1.
%t SequencePosition[Table[If[SequenceCount[IntegerDigits[n,6],{2,5}|{5,2}]>0,1,0],{n,1000}],{0,1}][[;;,2]] (* _Harvey P. Dale_, Aug 04 2023 *)
%Y Cf. A007092.
%K nonn,base
%O 1,1
%A _Clark Kimberling_