TORSION OF RATIONAL ELLIPTIC CURVES OVER CUBIC FIELDS AND SPORADIC POINTS ON X1(n)
نویسنده
چکیده
We classify the possible torsion structures of rational elliptic curves over cubic fields. Along the way we find a previously unknown torsion structure over a cubic field, Z/21Z, which corresponds to a sporadic point on X1(21) of degree 3, which is the lowest possible degree of a sporadic point on a modular curve X1(n).
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تاریخ انتشار 2012