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A039563 Numbers whose base-5 representation has the same number of 0's, 1's and 2's.

%I A039563 #20 Sep 08 2022 08:44:53
%S A039563 3,4,18,19,23,24,27,35,51,55,93,94,98,99,118,119,123,124,138,139,142,
%T A039563 147,178,179,190,195,202,210,227,235,258,259,266,271,278,279,290,295,
%U A039563 326,330,351,355,382,386,402,410,426,430,468,469,473,474,493,494,498
%N A039563 Numbers whose base-5 representation has the same number of 0's, 1's and 2's.
%H A039563 Robert Israel, <a href="/A039563/b039563.txt">Table of n, a(n) for n = 1..10000</a>
%p A039563 filter:= proc(n) local L,m;
%p A039563   L:= sort(select(`<=`,convert(n,base,5),2));
%p A039563   m:= nops(L)/3;
%p A039563   m::integer and L = [0$m,1$m,2$m];
%p A039563 end proc:
%p A039563 select(filter, [$1..1000]); # _Robert Israel_, Jan 17 2020
%t A039563 Select[Range[500],DigitCount[#,5,0]==DigitCount[#,5,1] == DigitCount[ #,5,2]&] (* _Harvey P. Dale_, Dec 24 2021 *)
%o A039563 (Magma) f:=func<n,b,c|Multiplicity(Intseq(n,b),c)>; [k:k in [1..500]|f(k,5,0) eq f(k,5,1) and f(k,5,0) eq f(k,5,2)]; // _Marius A. Burtea_, Jan 17 2020
%Y A039563 Cf. A007091 (numbers in base 5).
%K A039563 nonn,base,easy
%O A039563 1,1
%A A039563 _Olivier Gérard_