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%I #24 Apr 15 2016 13:58:49
%S 27,18,15,42,882
%N a(n) = smallest magic sum of any 3 X 3 magic square which contains exactly n cubes, or 0 if no such magic square exists.
%C For n >= 7, a(n) = 0 because the equation x^n + y^n = 2*z^n has no solution for n > 2 apart from the trivial x = y = z.
%D Richard K. Guy, Unsolved Problems in Number Theory, New York: Springer-Verlag, 2004, pp. 268-271.
%H Henri Darmon and Loic Merel, <a href="http://www.math.mcgill.ca/darmon/pub/Articles/Research/18.Merel/paper.pdf">Winding quotients and some variants of Fermat’s Last Theorem</a>
%H Arkadiusz Wesolowski, <a href="/A271450/a271450.txt">Examples of these magic squares</a>
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Fermat%27s_Last_Theorem">Fermat's Last Theorem</a>
%H <a href="/index/Mag#magic">Index entries for sequences related to magic squares</a>
%Y Cf. A269231.
%K nonn,fini,hard,more
%O 0,1
%A _Arkadiusz Wesolowski_, Apr 14 2016
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