A332531 - OEIS

A332531

Even numbers k such that A103230(k) is a perfect square.

442, 818, 1130, 1226, 1326, 1576, 2454, 3094, 3390, 3678, 3978, 4728, 4862, 5330, 5726, 5986, 6452, 7362, 7786, 7910, 8362, 8398, 8582, 8998, 9282, 10166, 10170, 10250, 11032, 11034, 11934, 12410, 12430, 13486, 13702, 14184, 14586, 15542, 15990, 17178, 17336

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OFFSET

1,1

COMMENTS

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).

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

EXAMPLE

442 is a term since A103230(442) = 2433600 = 1560^2.

MATHEMATICA

Select[2 * Range[9000], IntegerQ @ Sqrt[Abs[DivisorSigma[1, #, GaussianIntegers -> True]]^2] &]

CROSSREFS