A039047 - OEIS

%I #18 Jun 20 2021 15:06:15

%S 0,1,2,3,6,7,8,9,10,13,14,15,16,17,20,21,22,23,24,27,33,39,42,43,44,

%T 45,48,49,50,51,52,55,56,57,58,59,62,63,64,65,66,69,70,71,72,73,76,82,

%U 88,91,92,93,94,97,98,99,100,101,104,105,106,107,108,111,112,113,114

%N Numbers whose base-7 representation has the same number of 4's and 5's.

%H Daniel Starodubtsev, <a href="/A039047/b039047.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[Range[0,200],DigitCount[#,7,4]==DigitCount[#,7,5]&] (* _Harvey P. Dale_, Mar 22 2011 *)

%Y Cf. A007093.

%K nonn,base,easy

%O 1,3

%A _Olivier Gérard_