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%I #11 Oct 27 2023 22:00:46
%S 9,1,16,9,25,16,25,49,16,1,64,121,36,81,64,169,64,36,100,225,64,36,
%T 121,36,169,49,361,225,1,144,441,441,144,256,400,196,64,441,1,144,361,
%U 64,400,441,729,64,196,144,729,100,841,729,25,400,256,1225,100,729,1225
%N Squares mentioned in A054017.
%C If Chowla's function of n read (modulo n) is a nonzero square, print this square.
%C Chowla's function (A048050) = sum of divisors of n except 1 and n.
%H Amiram Eldar, <a href="/A054018/b054018.txt">Table of n, a(n) for n = 1..10000</a>
%t chowla[n_] := DivisorSigma[1, n] - n - 1; aQ[n_] := (c = chowla[n]) > 0 && IntegerQ @ Sqrt @ Mod[c, n]; Mod[chowla[#], #] & /@ Select[Range[1000], aQ] (* _Amiram Eldar_, Aug 28 2019 *)
%Y Cf. A048050, A054013, A054017, A054019.
%K nonn
%O 1,1
%A _Asher Auel_, Jan 19 2000
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