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 A232490 #21 Jun 20 2025 10:44:34 %S A232490 1,2,3,4,5,7,8,9,10,11,12,13,14,15,17,18,19,20,21,22,23,24,25,27,28, %T A232490 29,30,31,32,33,34,35,37,38,39,40,41,42,43,44,45,47,48,49,50,51,52,53, %U A232490 54,55,56,58,59,60,61,62,63,64,65,66,68,69,70,71,72,73,74,75,76,78,79,80,81,82,83,84,85,86,88,89,90,91,92,93 %N A232490 Numbers k such that 10^k is of the form m + sum of digits of m. %D A232490 M. Gardner, Time Travel and Other Mathematical Bewilderments. Freeman, NY, 1988, pp. 115-117 and 122. %D A232490 D. R. Kaprekar, Puzzles of the Self-Numbers. 311 Devlali Camp, Devlali, India, 1959. %D A232490 D. R. Kaprekar, The Mathematics of the New Self Numbers (Part V). 311 Devlali Camp, Devlali, India, 1967. %H A232490 Donovan Johnson, <a href="/A232490/b232490.txt">Table of n, a(n) for n = 1..10000</a> %H A232490 T. Trotter, <a href="http://www.trottermath.net/numthry/charlene.html">Charlene Numbers</a> %H A232490 <a href="/index/Coi#Colombian">Index entries for Colombian or self numbers and related sequences</a> %Y A232490 Cf. A062028, A232489, A232491. %K A232490 nonn,base %O A232490 1,2 %A A232490 _N. J. A. Sloane_, Dec 01 2013 %E A232490 Terms a(16) onward from _Max Alekseyev_, Dec 02 2013