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 A057533 #11 Oct 27 2023 22:00:46 %S A057533 48,75,92,140,146,176,195,215,255,267,287,312,332,369,386,407,411,519, %T A057533 527,551,627,734,744,818,972,973,984,1027,1050,1078,1096,1149,1175, %U A057533 1185,1387,1408,1472,1474,1535,1575,1648,1651,1784,1792,1880,1888,1891 %N A057533 Values of n for which iteration of Chowla's function loops. %C A057533 Chowla's function (A048050) = sum of divisors of n except 1 and n. %H A057533 Reinhard Zumkeller, <a href="/A057533/b057533.txt">Table of n, a(n) for n = 1..1000</a> %o A057533 (Haskell) %o A057533 a057533 n = a057533_list !! (n-1) %o A057533 a057533_list = filter (\z -> p z [z]) [1..] where %o A057533 p x ts = y > 0 && (y `elem` ts || p y (y:ts)) where y = a048050 x %o A057533 -- _Reinhard Zumkeller_, Feb 09 2013 %Y A057533 Cf. A048050. %Y A057533 Cf. A005276 (subsequence). - _Reinhard Zumkeller_, Feb 09 2013 %K A057533 nonn %O A057533 1,1 %A A057533 _Asher Auel_, Sep 03 2000