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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.

A051347 Numbers that are the sum of two (possibly negative) cubes in at least 2 ways.

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%I A051347 #18 Jan 03 2016 15:31:58
%S A051347 91,152,189,217,513,721,728,999,1027,1216,1512,1729,1736,2457,3087,
%T A051347 3367,4104,4706,4921,4977,5103,5256,5768,5824,5859,6832,7657,7992,
%U A051347 8216,8587,8911,9728,9919,10621,10712,11375,12096,12663,12691,12824,13832,13851
%N A051347 Numbers that are the sum of two (possibly negative) cubes in at least 2 ways.
%H A051347 Alois P. Heinz, <a href="/A051347/b051347.txt">Table of n, a(n) for n = 1..1000</a>
%e A051347 91 = 3^3 + 4^3 = (-5)^3 + 6^3; 152 = 3^3 + 5^3 = (-4)^3 + 6^3; 189 = 4^3 + 5^3 = (-3)^3 + 6^3; ...
%t A051347 ok[n_] := If[Length[PowersRepresentations[n, 2, 3]] >= 2, True, r = Reduce[n == x^3 + y^3, {x, y}, Integers]; If[r === False, False, Length[Union[Sort /@ ({x, y} /. {ToRules[r]})]] >= 2]]; Select[Range[13860], If[ok[#], Print[#]; True, False] &] (* _Jean-François Alcover_, Apr 11 2011 *)
%o A051347 (PARI) is(n)=#thue(thueinit(z^3+1),n)>=2 \\ _Ralf Stephan_, Oct 18 2013
%Y A051347 Cf. A051383, A051384.
%K A051347 nonn,nice
%O A051347 1,1
%A A051347 _Colin Mallows_
%E A051347 Extended by _Ray Chandler_, Jan 30 2009