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 A233929 #18 Dec 25 2013 11:56:44
%S A233929 1,1,7,2,3,2401,5,4,7,18,21,9604,6,9,13,8,44,21609,10,18,19,289,36,
%T A233929 9604,14,162,57,72,12,2614689,29,16,21,625,63,38416,22,4608,37,18,27,
%U A233929 21609,20,289,43,36,50,38416,33,196,111,162,157,28561,34,1296,28,49
%N A233929 Smallest x such that sigma(x) == n-1 (mod n).
%C A233929 Right subdiagonal of A074625.
%C A233929 Records values are: 1, 7, 2401, 9604, 21609, 2614689, 21215236, 36324729, 53304601, 338964921, 431642176, 528264256, 1307979556, ... obtained at indices: 1, 3, 6, 12, 18, 30, 60, 210, 288, 384, 534, 630, 732. - _Michel Marcus_, Dec 22 2013
%H A233929 Michel Marcus and Donovan Johnson, <a href="/A233929/b233929.txt">Table of n, a(n) for n = 1..3000</a> (first 800 terms from Michel Marcus)
%o A233929 (PARI) a(n) = {x = 1; while ((sigma(x) % n) != (n - 1), x++); x;} \\ _Michel Marcus_, Dec 18 2013
%Y A233929 Cf. A000203, A070982, A074625.
%K A233929 nonn
%O A233929 1,3
%A A233929 _Michel Marcus_, Dec 18 2013