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 A045203 #17 May 21 2023 00:20:46 %S A045203 4,9,14,19,21,22,23,34,39,44,46,47,48,59,64,69,71,72,73,84,89,94,96, %T A045203 97,98,106,107,108,111,112,113,116,117,118,159,164,169,171,172,173, %U A045203 184,189,194,196,197,198,209,214,219,221,222,223 %N A045203 Numbers whose base-5 representation contains no 0's and exactly one 4. %H A045203 Vincenzo Librandi, <a href="/A045203/b045203.txt">Table of n, a(n) for n = 1..1000</a> %t A045203 Select[Range[300],DigitCount[#,5,0]==0&&DigitCount[#,5,4]==1&] (* _Harvey P. Dale_, Jun 24 2014 *) %Y A045203 Cf. A007091. %K A045203 nonn,base %O A045203 1,1 %A A045203 _Clark Kimberling_