%I #16 Jun 25 2021 01:42:40
%S 0,2,3,4,5,7,8,15,18,20,21,22,23,25,26,27,29,30,31,32,34,35,36,38,39,
%T 40,41,43,44,45,47,48,49,50,52,53,55,63,65,66,67,68,70,71,72,74,75,76,
%U 77,79,80,87,105,114,123,132,135,137,138,139,140,142,143,150,159,162
%N Numbers whose base-9 representation has the same number of 1's and 6's.
%H Robert Israel, <a href="/A039088/b039088.txt">Table of n, a(n) for n = 1..10000</a>
%p filter:= proc(n) local L;
%p L:= convert(n,base,9);
%p numboccur(1,L) = numboccur(6,L)
%p end proc:
%p select(filter, [$0..1000]); # _Robert Israel_, Mar 13 2018
%o (PARI) isok(n) = {my(d = digits(n, 9)); #select(x->(x==1), d) == #select(x->(x==6), d);} \\ _Michel Marcus_, Mar 13 2018
%Y Cf. A007095.
%K nonn,base,easy
%O 1,2
%A _Olivier GĂ©rard_