This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A332571 #10 Feb 17 2020 09:36:31
%S A332571 5,9,13,21,33,119,187,203,287,543,699,807,831,843,879,939,951,1011,
%T A332571 1047,1059,1119,1167,1191,1263,1299,1311,1347,1383,1563,1671,1767,
%U A332571 1769,1961,2117,2139,2173,2257,2451,2501,2581,2679,2813,2929,2967,2993,3161,3233,3243
%N A332571 Numbers that are primitive norm-abundant in Gaussian integers.
%C A332571 Numbers that are norm-abundant (A332570) in Gaussian integers and having no norm-abundant proper divisor.
%D A332571 Miriam Hausman, On Norm Abundant Gaussian Integers, The Journal of the Indian Mathematical Society, Vol. 49 (1987), pp. 119-123.
%D A332571 József Sándor, Dragoslav S. Mitrinovic and Borislav Crstici, Handbook of Number Theory I, Springer Science & Business Media, 2005, chapter III, page 120.
%H A332571 Amiram Eldar, <a href="/A332571/b332571.txt">Table of n, a(n) for n = 1..10000</a>
%H A332571 Robert Spira, <a href="https://doi.org/10.1080/00029890.1961.11989634">The Complex Sum of Divisors</a>, The American Mathematical Monthly, Vol. 68, No. 2 (1961), pp. 120-124.
%e A332571 5 is primitive norm-abundant since it is norm-abundant, sigma(5) = 4 + 8*i and N(4 + 8*i) = 4^2 + 8^2 = 80 > 2 * 5^2 = 50, and none of the proper divisors of 5, {1, 1 + 2*i, 2 + i}, are norm-abundant: N(sigma(1)) = 1 < 2 * 1^2, N(sigma(1 + 2*i)) = N(2 + 2*i) = 8 < 2 * N(1 + 2*i) = 10, and N(sigma(2 + i)) = N(3 + i) = 10 = 2 * N(2 + i). (sigma(k) = A103228(k) + i*A103229(k) is the sum of divisors of k in Gaussian integers, i is the imaginary unit, and N(z) = Re(z)^2 + Im(z)^2 is the norm of the complex number z.)
%t A332571 normAbQ[z_] := normAbQ[z] = Abs[DivisorSigma[1, z, GaussianIntegers -> True]]^2 > 2*Abs[z]^2; primNormAbQ[z_] := normAbQ[z] && !AnyTrue[Most[Divisors[z, GaussianIntegers -> True]], normAbQ]; Select[Range[1000], primNormAbQ]
%Y A332571 Cf. A091191, A103228, A103229, A103230, A332570.
%K A332571 nonn
%O A332571 1,1
%A A332571 _Amiram Eldar_, Feb 16 2020