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 A024634 #17 Jul 31 2025 03:51:18 %S A024634 0,1,2,3,4,40,41,42,43,44,430,431,432,433,434,4320,4321,4322,4323, %T A024634 4324,43210,43211,43212,43213,43214,432100,432101,432102,432103, %U A024634 432104,432140,432141,432142,432143,432144,4321030,4321031,4321032,4321033,4321034 %N A024634 n written in fractional base 5/4. %C A024634 To represent a number in base b, if a digit exceeds b-1, subtract b and carry 1. In fractional base a/b, subtract a and carry b. %H A024634 Amiram Eldar, <a href="/A024634/b024634.txt">Table of n, a(n) for n = 0..10000</a> %H A024634 <a href="/index/Ba#base_fractional">Index entries for sequences related to fractional bases</a>. %t A024634 a[n_] := a[n] = If[n == 0, 0, 10 * a[4 * Floor[n/5]] + Mod[n, 5]]; Array[a, 50, 0] (* _Amiram Eldar_, Jul 31 2025 *) %o A024634 (PARI) a(n) = if(n == 0, 0, 10 * a(n\5 * 4) + n % 5); \\ _Amiram Eldar_, Jul 31 2025 %Y A024634 Cf. A245335, A245357. %K A024634 nonn,base,easy %O A024634 0,3 %A A024634 _David W. Wilson_