How to find generators to group $E(\mathbb Q) $ of following elliptic curves $E:y^2=x^3-198 $, $E:y^2=x^3-122 $. Thank you in advance.
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What do you know, and what have you tried? – Lubin Oct 24 '14 at 04:38
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I Just used Sage software to find generators but its not giving answer. So, I need help to find generators – MKJ Oct 25 '14 at 04:32
2 Answers
1
The rank of both curves are $0$. Extensive computations for all curves $y^2=x^3+k$ in the range $|k|\leq10^5$ was made by Gebel, Pethö and Zimmer in their paper On Mordell's Equation which you may find here
http://www.inf.unideb.hu/~pethoe/cikkek/67_MORDELL.pdf
The table of their results may be resurrected here
http://web.archive.org/web/20040816044914/http://emmy.math.uni-sb.de/~simath/MORDELL/MORDELL-
Jesper Petersen
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This is a late comment, showing that sage (at least after years) provides the correct information...
sage: E = EllipticCurve(QQ, [0, -198])
sage: E
Elliptic Curve defined by y^2 = x^3 - 198 over Rational Field
sage: E.rank(only_use_mwrank=False)
0
sage: E.torsion_order()
1
and
sage: E = EllipticCurve(QQ, [0, -122])
sage: E
Elliptic Curve defined by y^2 = x^3 - 122 over Rational Field
sage: E.rank(only_use_mwrank=False)
0
sage: E.torsion_order()
1
To make the code work, the option only_use_mwrank=False was inserted.
dan_fulea
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