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 A024664 #11 Aug 04 2025 02:17:19 %S A024664 0,1,2,3,4,5,6,7,8,9,90,91,92,93,94,95,96,97,98,99,980,981,982,983, %T A024664 984,985,986,987,988,989,9870,9871,9872,9873,9874,9875,9876,9877,9878, %U A024664 9879,98760,98761,98762,98763,98764,98765,98766,98767,98768,98769,987650 %N A024664 n written in fractional base 10/9. %C A024664 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 A024664 Amiram Eldar, <a href="/A024664/b024664.txt">Table of n, a(n) for n = 0..10000</a> %H A024664 <a href="/index/Ba#base_fractional">Index entries for sequences related to fractional bases</a>. %t A024664 a[n_] := a[n] = If[n == 0, 0, 10 * a[9 * Floor[n/10]] + Mod[n, 10]]; Array[a, 50, 0] (* _Amiram Eldar_, Aug 04 2025 *) %o A024664 (PARI) a(n) = if(n == 0, 0, 10 * a(n\10 * 9) + n % 10); \\ _Amiram Eldar_, Aug 04 2025 %Y A024664 Cf. A245339. %K A024664 nonn,base,easy %O A024664 0,3 %A A024664 _David W. Wilson_