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Timeline for On the equation $9x^3+y^3=z^2+3$

Current License: CC BY-SA 4.0

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Feb 22 at 21:27 comment added Denis Shatrov A typo in second sentence: If $p \mid y$ then $p \mid x$.
Feb 22 at 21:15 comment added Denis Shatrov @TimothyChow If $y$ is not divisible by $p$, then $3 \equiv (\frac{-3x}{y})^3 \pmod{p}$ which is impossible. If $y \mid p$, then $x \mid p$. $9(x/p)^3 + (y/p)^3 = (z^2 + 3)/p^3$. We can continue this process until we get $9(x/p^k)^3 + (y/p^k)^3 = (z^2 + 3)/(p^{3k}) $ where $(z^2 + 3)/(p^{3k})$ is not divisible by $p$. Hence, $\nu_p(z^2 + 3) = 3k$.
Feb 22 at 19:31 comment added Timothy Chow Can you say more about why $3$ being a cubic nonresidue mod $p$ implies that $3\mid \nu_p(z^2+3)$? I don't follow that step.
Feb 20 at 10:40 history edited Denis Shatrov CC BY-SA 4.0
fixed typo
Feb 19 at 12:43 vote accept Bogdan Grechuk
Feb 19 at 10:30 history answered Denis Shatrov CC BY-SA 4.0