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Timeline for Status of $x^3+y^3+z^3=6xyz$

Current License: CC BY-SA 4.0

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Apr 4, 2021 at 5:13 answer added Tomita timeline score: 2
Apr 1, 2021 at 12:21 answer added Erik Dofs timeline score: 4
Feb 27, 2021 at 16:28 answer added Sam timeline score: 1
Feb 23, 2021 at 5:40 vote accept Haran
Feb 22, 2021 at 15:01 answer added Timothy Chow timeline score: 15
Feb 22, 2021 at 12:04 comment added Haran @Wojowu Thank you :)
Feb 22, 2021 at 12:03 comment added Wojowu The method to transform an arbitrary smooth cubic into a Weierstrass form is standard and is explained for instance in the lovely book by Silverman-Tate, see section 1.3 or appendix B there. It is also implemented in Sage as EllipticCurve_from_cubic
Feb 22, 2021 at 9:46 comment added Haran @NoamD.Elkies Thank you for your response! If possible, could you let me know what substitution you made to transform the given Diophantine Equation into an Elliptic Curve? Thanks in advance.
Feb 22, 2021 at 2:57 comment added David Roberts @NoamD.Elkies and even more characters can be used for human-readable information that might be of use to someone down the track. :-)
Feb 22, 2021 at 2:55 history edited David Roberts CC BY-SA 4.0
added 118 characters in body; edited tags
Feb 22, 2021 at 2:45 comment added Noam D. Elkies @Gerry Myerson Fixed this now (seems that 9 of the 10 characters can be invisible whitespace ☺)
Feb 22, 2021 at 2:41 history edited Noam D. Elkies CC BY-SA 4.0
Correct a typo signaled by **Gerry Myerson** ($z^3$, not $z^2$)
Feb 21, 2021 at 22:22 comment added Gerry Myerson In the first line of the body of the question, $z^2$ should be $z^3$. (I would just edit this myself, but edits have to be at least ten characters.)
Feb 21, 2021 at 20:07 comment added Noam D. Elkies @dodd as usual, each rational point on the elliptic curve corresponds to a unique primitive solution (up to multiplying $(x,y,z)$ by $-1$). $$ $$ Haran: The positive solutions constitute one of two connected components of the real locus of the elliptic curve. Since the generator is on that component (and the identity is not), its odd multiples again yield positive solutions. The next batches of positive solutions are permutations of $(1817, 3258, 5275)$ and $(4904676969, 10840875082, 15051171563)$.
Feb 21, 2021 at 19:37 comment added markvs Usually in this case one is interested in co-prime solutions, @Lubin. Like in the paper linked in the OP.
Feb 21, 2021 at 19:34 comment added Lubin But rational solutions to the Weierstrass equation will always correspond to integer solutions of the homogeneous equation in OP’s question, @dodd .
Feb 21, 2021 at 19:34 comment added Haran @NoamD.Elkies Can we say anything specific about positive solutions alone?
Feb 21, 2021 at 19:31 comment added markvs I am not sure the OP is interested in rational (not integer) solutions.
Feb 21, 2021 at 19:19 history edited LSpice CC BY-SA 4.0
Name of paper and DOI
Feb 21, 2021 at 18:57 comment added Noam D. Elkies This curve has a rational point at $(x:y:z)=(1:2:3)$ (and infinitely many others, such as $(19:21:-52)$ ). If I did this right it's isomorphic with $Y^2 + Y = X^3 - 54 X - 88$, which has torsion ${\bf Z} / 3{\bf Z}$ (as usual in this family) and rank 1, see e.g. <lmfdb.org/EllipticCurve/Q/189/b/2>. So yes, one can start with $(1:2:3)$ and its permutations and generate all rational solutions with "chords and tangents".
Feb 21, 2021 at 18:29 history asked Haran CC BY-SA 4.0