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 A173494 #9 Apr 16 2025 04:34:59
%S A173494 1,2,5,7,11,13,17,19,23,29,31,37,38,41,43,47,53,58,59,61,65,67,71,73,
%T A173494 74,77,79,82,83,85,86,89,91,97,101,103,106,107,109,113,127,131,133,
%U A173494 134,137,139,145,146,149,151,157,163,167,173,178,179,181,185,187,191,193,197
%N A173494 Numbers m such that no square greater than 1 can be written as sum of distinct divisors of m.
%C A173494 2546 is the smallest term having more than two prime factors: 2546 = 2*19*67.
%H A173494 Amiram Eldar, <a href="/A173494/b173494.txt">Table of n, a(n) for n = 1..10000</a>
%F A173494 A173493(a(n)) = 1.
%t A173494 q[m_] := Module[{d = Divisors[m], sum, sq, x}, sum = Plus @@ d; sq = Range[2, Floor[Sqrt[sum]]]^2; Total[CoefficientList[Product[1 + x^i, {i, d}], x][[1 + sq]]] == 0]; Select[Range[200], q] (* _Amiram Eldar_, Apr 16 2025 *)
%Y A173494 Cf. A173493.
%Y A173494 A045344 is a subsequence (the primes except 3).
%K A173494 nonn
%O A173494 1,2
%A A173494 _Reinhard Zumkeller_, Feb 20 2010