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 A051280 #24 Feb 16 2019 01:12:19
%S A051280 3,25,40,49,54,121,125,135,140,169,189,216,220,250,260,289,297,340,
%T A051280 351,361,375,380,400,459,460,500,513,529,580,620,621,675,729,740,770,
%U A051280 783,820,837,841,860,875,882,910,940,961,999,1060,1107,1152,1161,1180,1188,1190
%N A051280 Numbers n such that n = k/d(k) has exactly 3 solutions, where d(k) = number of divisors of k.
%C A051280 Many terms are of the form a(k) * p^m/(m+1), where p is coprime to the three solutions for k. The sequence of "primitive" terms (i.e. not expressible this way) begins 3, 40, 54, 125, 135, 216, 250.... Are there any such numbers that admit a fourth solution? - _Charlie Neder_, Feb 13 2019
%H A051280 T. D. Noe, <a href="/A051280/b051280.txt">Table of n, a(n) for n = 1..1000</a>
%e A051280 There are exactly 3 numbers k, 9, 18 and 24, with k/d(k) = 3.
%t A051280 (Select[Table[k / Length @ Divisors[k], {k, 1, 200000}], IntegerQ] // Sort // Split // Select[#, Length[#] == 3 &] &)[[All, 1]][[1 ;; 53]] (* _Jean-François Alcover_, Apr 22 2011 *)
%Y A051280 Cf. A033950, A036763, A051278, A051279, A051346.
%K A051280 nonn,easy,nice
%O A051280 1,1
%A A051280 _N. J. A. Sloane_, _R. K. Guy_, _David W. Wilson_