This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A044956 #15 Feb 22 2019 06:24:56
%S A044956 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 A044956 78,81,85,89,92,97,98,100,106,107,112,113,114,115,116,117,118,121,122,
%U A044956 128,130,135,138,142,146,147,150,155,157,163,164
%N A044956 Numbers with no two equally numerous base 7 digits.
%e A044956 106 in base 7 is 211, which has one more 1 than it has 2's.
%e A044956 107 in base 7 is 212, which has one more 2 than it has 1's.
%e A044956 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 A044956 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 A044956 Cf. A007093 (numbers in base 7), A023802.
%K A044956 nonn,base
%O A044956 1,2
%A A044956 _Clark Kimberling_