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 A064708 #21 Oct 19 2017 03:13:56
%S A064708 6,14,20,33,54,91,141,141
%N A064708 Initial term of run of (at least) n consecutive numbers with just 2 distinct prime factors.
%C A064708 It can be shown by an application of Mihailescu's theorem that a(12) does not exist, since then there would be two 3-smooth numbers close together (it suffices to check up to 2*3^3).
%C A064708 If a(9) exists, it is greater than 10^30. - _Don Reble_, Mar 02 2003
%C A064708 If a(9) exists, it is greater than 10^3000. - _Charles R Greathouse IV_, Apr 22 2009
%C A064708 Eggleton and MacDougall prove that no terms exist beyond a(9) and conjecture that a(9) does not exist. - _Jason Kimberley_, Jul 08 2017
%H A064708 Roger B. Eggleton and James A. MacDougall, <a href="http://www.jstor.org/stable/27643119">Consecutive integers with equally many principal divisors</a>, Math. Mag. 81 (2008), 235-248. [_T. D. Noe_, Oct 13 2008]
%e A064708 6 = 2*3; 14 = 2*7 and 15 = 3*5; 20 = 2^2*5, 21 = 3*7 and 22 = 2*11; 33 = 3*11, 34 = 2*17, 35 = 5*7 and 36 = (2*3)^2; etc.
%t A064708 Function[s, Function[t, Reverse@ FoldList[If[#2 > #1, #1, #2] &, Reverse[#]] &@ Map[t[[First@ FirstPosition[t[[All, -1]], k_ /; k == #] ]] &, Range[0, Max@ t[[All, -1]] ] ][[All, 1]] ]@ Join[{{First@ s, 0}, {#[[1, 1, 1]], 1}}, Rest@ Map[{#[[1, 1]], Length@ # + 1} &, #, {1}]] &@ SplitBy[Partition[Select[#, Last@ # == 1 &][[All, 1]], 2, 1], Differences] &@ Map[{First@ #, First@ Differences@ #} &, Partition[s, 2, 1]]]@ Select[Range[10^5], PrimeNu[#] == 2 &] (* _Michael De Vlieger_, Jul 17 2017 *)
%Y A064708 Cf. A064709.
%K A064708 nonn,fini
%O A064708 1,1
%A A064708 _Robert G. Wilson v_, Oct 13 2001