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%I #15 Feb 22 2019 06:24:56
%S 1,2,3,4,5,6,8,16,24,32,40,48,49,50,56,57,58,59,60,61,62,64,65,71,73,
%T 78,81,85,89,92,97,98,100,106,107,112,113,114,115,116,117,118,121,122,
%U 128,130,135,138,142,146,147,150,155,157,163,164
%N Numbers with no two equally numerous base 7 digits.
%e 106 in base 7 is 211, which has one more 1 than it has 2's.
%e 107 in base 7 is 212, which has one more 2 than it has 1's.
%e 108 in base 7 is 213. Since each digit occurs as many times as the others (once each), 108 is not in the sequence.
%t enb7Q[n_] := Module[{t = Tally[IntegerDigits[n, 7]][[All, 2]]}, Length[t] == Length[Union[t]]]; Select[Range[200], enb7Q] (* _Harvey P. Dale_, Jul 26 2018 *)
%Y Cf. A007093 (numbers in base 7), A023802.
%K nonn,base
%O 1,2
%A _Clark Kimberling_
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