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fivemack · 2009-09-16, 15:53

Yes, finding points on elliptic curves is a deep subject; it's just about practical for smallish curves, but the algorithms are real pigs to implement and you need lots of them. If you can afford $400, buy a copy of the Magma computer algebra system; for small examples you can use

http://magma.maths.usyd.edu.au/calc/

and say for example

E:=EllipticCurve([0,0,1,-7,6]);
Rank(E);
IntegralPoints(E);

I can't quite remember the sequence of manipulations required to convert a quartic polynomial and a single rational point into an EllipticCurve and a map back to the y^2=quartic model.

2009-09-16, 15:53	#3
fivemack (loop (#_fork)) Feb 2006 Cambridge, England 2·3,191 Posts	Yes, finding points on elliptic curves is a deep subject; it's just about practical for smallish curves, but the algorithms are real pigs to implement and you need lots of them. If you can afford $400, buy a copy of the Magma computer algebra system; for small examples you can use http://magma.maths.usyd.edu.au/calc/ and say for example E:=EllipticCurve([0,0,1,-7,6]); Rank(E); IntegralPoints(E); I can't quite remember the sequence of manipulations required to convert a quartic polynomial and a single rational point into an EllipticCurve and a map back to the y^2=quartic model.