## Cryptology ePrint Archive: Report 2004/129

Generalizing Kedlaya's order counting based on Miura Theory

Joe Suzuki

Abstract: K. Kedlaya proposed an method to count the number of ${\mathbb F}_q$-rational points in a hyper-elliptic curve, using the Leschetz fixed points formula in Monsky-Washinitzer Cohomology. The method has been extended to super-elliptic curves (Gaudry and G\"{u}rel) immediately, to characteristic two hyper-elliptic curves, and to $C_{ab}$ curves (J. Denef, F. Vercauteren). Based on Miura theory, which is associated with how a curve is expressed as an affine variety, this paper applies Kedlaya's method to so-called strongly telescopic curves which are no longer plane curves and contain super-elliptic curves as special cases.

Category / Keywords: foundations / Kedlaya, Miura, order counting, elliptic curves