The only whole number solution to the Diophantine equation
 |
is 
,
.
This theorem was offered as a problem by Fermat, who suppressed his own proof.
Fermat Elliptic Curve Theorem
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Cite this as:
Weisstein, Eric W. "Fermat Elliptic Curve Theorem." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/FermatEllipticCurveTheorem.html