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

Author

Arkadiusz Wesolowski, Apr 14 2016

Keywords

• nonn
• fini
• hard
• more

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

• 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.