John Cremona (Maths) on Mon, 7 Sep 1998 09:54:01 +0100


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Re: Pari Bug (elltors)


If you change to a standard minimal model with

g=ellglobalred(v)
w=ellchangecurve(v,g[2])

and then  do

elltors(w)

you correctly get the 6 torsion points.  I have not looked at the Pari
torsion code; perhaps it is happening because the coefficients are
rational but not integral, and it uses Lutz-Nagell which should apply
to integral equations.

-- 
John Cremona
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