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%I #12 Jun 25 2022 17:46:36
%S 1,1,2,1,1,2,2,1,1,3,2,2,1,2,2,1,3,1,2,1,4,6,2,2,1,1,2,2,1,6,4,3,4,3,
%T 4,1,1,2,2,3,1,4,2,2,1,6,4,2,1,1,6,7,3,2,6,2,4,3,2,2,1,4,2,1,2,12,2,3,
%U 4,12,6,1,1,1,2,2,4,2,4,1,11,3,2,4,6,2,2,6,3,3,4,2,8,12,2,6,7,3,2,1,1,6,2,1,8
%N Square root of the largest square dividing the sum of divisors of n: a(n) = A000188(sigma(n)).
%H Antti Karttunen, <a href="/A326038/b326038.txt">Table of n, a(n) for n = 1..65537</a>
%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F a(n) = A000188(A000203(n)) = A000196(A326039(n)).
%t Table[Last[Select[Sqrt[#]&/@Divisors[DivisorSigma[1,n]],IntegerQ]],{n,120}] (* _Harvey P. Dale_, Jun 25 2022 *)
%o (PARI)
%o A000188(n) = core(n, 1)[2]; \\ From A000188
%o A326038(n) = A000188(sigma(n));
%Y Cf. A000188, A000196, A326038, A326039, A326040.
%K nonn
%O 1,3
%A _Antti Karttunen_, Jun 05 2019