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arXiv · 0810.5181

Rational torsion in elliptic curves and the cuspidal subgroup

Amod Agashe
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Abstract

Let $A$ be an elliptic curve over $\Q$ of square free conductor $N$. We prove that if $A$ has a rational torsion point of prime order $r$ such that $r$ does not divide $6N$, then $r$ divides the order of the cuspidal subgroup of $J_0(N)$.

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Amod Agashe. 2008-10-29. Rational torsion in elliptic curves and the cuspidal subgroup. https://arxiv.org/abs/0810.5181

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