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%I #9 Aug 25 2021 05:09:43
%S 18,30,67,79,116,132,165,177,216,226,263,275,312,324,361,373,410,422,
%T 459,475,508,520,559,569,606,618,655,667,704,716,753,765,802,818,851,
%U 863,930,949,961,998,1010,1047,1059,1096,1108
%N Numbers k such that 2 and 4 occur juxtaposed in the base-7 representation of k but not of k+1.
%t Transpose[SequencePosition[Table[If[SequenceCount[IntegerDigits[n,7],{2,4}]>0 || SequenceCount[IntegerDigits[n,7],{4,2}]>0,1,0],{n,1200}],{1,0}]][[1]] (* The program uses the SequencePosition and SequenceCount functions from Mathematica version 10 *) (* _Harvey P. Dale_, Mar 10 2016 *)
%Y Cf. A007093.
%K nonn,base
%O 1,1
%A _Clark Kimberling_
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