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 A064593 #12 Jan 05 2025 19:51:36 %S A064593 186076800,3456573120,18924364800,325377803520,2666567816640, %T A064593 8538872307840,11169839116800 %N A064593 Nonunitary triply perfect numbers: the sum of the nonunitary divisors of n is 3n; i.e., sigma(n) - usigma(n) = 3n. %C A064593 There are no others up to 1.6*10^13, but there are at least 20 larger ones, between 87916260096000 and 19424258892617980729341453189120. %C A064593 Ligh & Wall found a(1), a(4) and a(5). - _Amiram Eldar_, Sep 27 2018 %H A064593 Steve Ligh and Charles R. Wall, <a href="https://web.archive.org/web/2024*/https://www.fq.math.ca/Scanned/25-4/ligh.pdf">Functions of Nonunitary Divisors</a>, Fibonacci Quarterly, Vol. 25 (1987), pp. 333-338. %Y A064593 Cf. A048146, A064591, A064592, A064594, A064595, A064596. %K A064593 nonn,hard %O A064593 1,1 %A A064593 _Dean Hickerson_, Sep 25 2001