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 A333639 #17 May 10 2024 03:35:16
%S A333639 1,6,672,1638,30240,32760,2178540,17428320,23569920,29410290,45532800,
%T A333639 714954240,1379454720,14182439040,19209881600,30600708096,51001180160,
%U A333639 57575890944,57629644800,153003540480,206166804480,403031236608,465036042240,482476262400
%N A333639 Numbers m such that g(m) = (m * tau(m) / sigma(m)), h(m) = (m * sigma(m)) / tau(m) and k(m) = (tau(m) * sigma(m)) / m are all integers.
%C A333639 Corresponding sequences of values of integers g(m), h(m) and k(m): {1, 2, 8, 9, 24, 24, 54, 96, 80, 81, 96, 200, ...}, {1, 18, 56448, 298116, 38102400, 44717400, 87889565400, 3164024354400, ...}, {1, 8, 72, 64, 384, 384, 864, 1944, 1280, 1024, 1536, 4608, 2304, 9600, 2916, ...}.
%H A333639 Amiram Eldar, <a href="/A333639/b333639.txt">Table of n, a(n) for n = 1..34</a> (terms below 10^14)
%t A333639 Select[Range[10^5], Divisible[# * (d = DivisorSigma[0, #]), (s = DivisorSigma[1, #])] && Divisible[# * s, d] && Divisible[d * s, #] &] (* _Amiram Eldar_, Mar 31 2020 *)
%o A333639 (Magma) [m: m in [1..10^5] | IsIntegral((m * #Divisors(m)) / &+Divisors(m)) and IsIntegral((&+Divisors(m) * m) / #Divisors(m)) and IsIntegral((&+Divisors(m) * #Divisors(m)) / m)]
%Y A333639 Subsequence of harmonic numbers (A001599).
%Y A333639 Intersection of A001599, A333638 and A071707.
%Y A333639 Cf. A000005, A000203.
%K A333639 nonn
%O A333639 1,2
%A A333639 _Jaroslav Krizek_, Mar 30 2020