A039018 - OEIS

%I #16 Jun 20 2021 08:36:33

%S 1,2,4,5,7,8,10,11,13,14,16,17,18,25,26,28,29,31,32,34,35,39,43,44,46,

%T 47,49,50,52,53,54,61,62,64,65,67,68,70,71,75,79,80,82,83,85,86,88,89,

%U 90,97,98,100,101,103,104,106,107,109,110,112,113,114,120,132,138,147

%N Numbers whose base-6 representation has the same number of 0's and 3's.

%H Robert Israel, <a href="/A039018/b039018.txt">Table of n, a(n) for n = 1..10000</a>

%p filter:= proc(n) local L;

%p   L:= convert(n,base,6);

%p   numboccur(0,L)=numboccur(3,L)

%p end proc:

%p select(filter, [$1..200]); # _Robert Israel_, May 30 2018

%t Select[Range[200],DigitCount[#,6,0]==DigitCount[#,6,3]&] (* _Harvey P. Dale_, Feb 25 2015 *)

%Y Cf. A007092 (numbers in base 6).

%K nonn,base,easy

%O 1,2

%A _Olivier Gérard_