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 A230853 #14 Feb 13 2023 16:11:40
%S A230853 0,2,6,16,26,34,44,54,62,72,98,108,116,126,136,144,154,180,190,198,
%T A230853 208,218,226,236,260,270,278,288,298,306,316,342,352,360,370,380,388,
%U A230853 398,424,434,442,452,462,470,480,504,514,522,532,542,550,560,586,596,604,614,624,632,642,668,678,686
%N A230853 Numbers n such that m + (sum of digits in base-3 representation of m) = n has exactly one solution.
%H A230853 Donovan Johnson, <a href="/A230853/b230853.txt">Table of n, a(n) for n = 1..10000</a>
%H A230853 <a href="/index/Coi#Colombian">Index entries for Colombian or self numbers and related sequences</a>
%t A230853 Select[Tally[Table[m+Total[IntegerDigits[m,3]],{m,0,700}]],#[[2]]==1&][[;;,1]] (* _Harvey P. Dale_, Feb 13 2023 *)
%Y A230853 Related base-3 sequences: A053735, A134451, A230641, A230642, A230643, A230853, A230854, A230855, A230856, A230639, A230640, A010063 (trajectory of 1)
%K A230853 nonn,base
%O A230853 1,2
%A A230853 _N. J. A. Sloane_, Oct 31 2013