Solving Thue equations without the full unit group

Hanrot, Guillaume

doi:10.1090/S0025-5718-99-01124-2

Solving Thue equations without the full unit group
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by Guillaume Hanrot PDF

Math. Comp. 69 (2000), 395-405 Request permission

Abstract:

The main problem when solving a Thue equation is the computation of the unit group of a certain number field. In this paper we show that the knowledge of a subgroup of finite index is actually sufficient. Two examples linked with the primitive divisor problem for Lucas and Lehmer sequences are given.

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