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%I #8 Feb 16 2020 02:43:48
%S 442,818,1130,1226,1326,1576,2454,3094,3390,3678,3978,4728,4862,5330,
%T 5726,5986,6452,7362,7786,7910,8362,8398,8582,8998,9282,10166,10170,
%U 10250,11032,11034,11934,12410,12430,13486,13702,14184,14586,15542,15990,17178,17336
%N Even numbers k such that A103230(k) is a perfect square.
%C The odd numbers k such that A103230(k) is a perfect square are the numbers that are divisible only by primes congruent to 3 mod 4 (A004614).
%H Amiram Eldar, <a href="/A332531/b332531.txt">Table of n, a(n) for n = 1..10000</a>
%e 442 is a term since A103230(442) = 2433600 = 1560^2.
%t Select[2 * Range[9000], IntegerQ @ Sqrt[Abs[DivisorSigma[1, #, GaussianIntegers -> True]]^2] &]
%Y Cf. A004614, A006532, A103230.
%K nonn
%O 1,1
%A _Amiram Eldar_, Feb 15 2020