%I #16 Jun 30 2021 01:53:45
%S 15,55,87,105,114,123,132,135,137,138,139,140,142,143,150,159,177,217,
%T 258,298,339,379,420,460,487,495,497,498,499,500,502,503,505,514,523,
%U 532,550,559,582,622,663,703,735,753,762,771,780,783,785,786,787,788
%N Numbers whose base-9 representation has the same nonzero number of 1's and 6's.
%H Robert Israel, <a href="/A039369/b039369.txt">Table of n, a(n) for n = 1..10000</a>
%p filter:= proc(n) local L,a1;
%p L:= convert(n,base,9);
%p a1:= numboccur(1,L);
%p a1 > 0 and numboccur(6,L)=a1
%p end proc:
%p select(filter, [$1..1000]); # _Robert Israel_, Sep 27 2018
%t Select[Range[1000],DigitCount[#,9,1]==DigitCount[#,9,6]>0&] (* _Harvey P. Dale_, Oct 15 2014 *)
%Y Cf. A007095.
%K nonn,base,easy
%O 1,1
%A _Olivier GĂ©rard_
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