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arXiv · 2302.00568

Halving formulae for points on elliptic curves

Lorenz Halbeisen·Norbert Hungerbuehler
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Abstract

Let $P$ be an arbitrary point on an elliptic curve over the complex numbers of the form $y^2=x^3+a_4\,x+a_6$ or of the form $y^2=x^3+a_2\,x^2+a_4\,x$. We provide explicit formulae to compute the points $P/2$, i.e., the points $Q$ such that $2*Q=P$.

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Lorenz Halbeisen, Norbert Hungerbuehler. 2023-02-01. Halving formulae for points on elliptic curves. https://arxiv.org/abs/2302.00568

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