This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A039014 #14 Jun 20 2021 14:57:36 %S A039014 0,1,3,5,6,8,14,15,16,18,22,25,26,28,30,31,33,39,40,41,43,47,54,59,69, %T A039014 70,71,73,75,76,78,80,81,83,89,90,91,93,97,102,107,110,111,113,117, %U A039014 125,126,128,130,131,133,139,140,141,143,147,150,151,153,155,156,158 %N A039014 Numbers whose base-5 representation has the same number of 2's and 4's. %H A039014 Daniel Starodubtsev, <a href="/A039014/b039014.txt">Table of n, a(n) for n = 1..10000</a> %t A039014 Select[Range[0,200],DigitCount[#,5,2]==DigitCount[#,5,4]&] (* _Harvey P. Dale_, Jul 17 2016 *) %Y A039014 Cf. A007091. %K A039014 nonn,base,easy %O A039014 1,3 %A A039014 _Olivier Gérard_