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Values of n for which iteration of Chowla's function loops.
3

%I #11 Oct 27 2023 22:00:46

%S 48,75,92,140,146,176,195,215,255,267,287,312,332,369,386,407,411,519,

%T 527,551,627,734,744,818,972,973,984,1027,1050,1078,1096,1149,1175,

%U 1185,1387,1408,1472,1474,1535,1575,1648,1651,1784,1792,1880,1888,1891

%N Values of n for which iteration of Chowla's function loops.

%C Chowla's function (A048050) = sum of divisors of n except 1 and n.

%H Reinhard Zumkeller, <a href="/A057533/b057533.txt">Table of n, a(n) for n = 1..1000</a>

%o (Haskell)

%o a057533 n = a057533_list !! (n-1)

%o a057533_list = filter (\z -> p z [z]) [1..] where

%o p x ts = y > 0 && (y `elem` ts || p y (y:ts)) where y = a048050 x

%o -- _Reinhard Zumkeller_, Feb 09 2013

%Y Cf. A048050.

%Y Cf. A005276 (subsequence). - _Reinhard Zumkeller_, Feb 09 2013

%K nonn

%O 1,1

%A _Asher Auel_, Sep 03 2000