A271450 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.

27, 18, 15, 42, 882

Offset

0,1

Comments

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.

References

Richard K. Guy, Unsolved Problems in Number Theory, New York: Springer-Verlag, 2004, pp. 268-271.

Links

Table of n, a(n) for n=0..4.

Henri Darmon and Loic Merel, Winding quotients and some variants of Fermat’s Last Theorem

Arkadiusz Wesolowski, Examples of these magic squares

Wikipedia, Fermat's Last Theorem

Index entries for sequences related to magic squares

Crossrefs

Cf. A269231.

Sequence in context: A317106 A033347 A173896 * A169733 A105325 A277270

Adjacent sequences: A271447 A271448 A271449 * A271451 A271452 A271453

Keyword

nonn,fini,hard,more

Author

Arkadiusz Wesolowski, Apr 14 2016

Status

approved