Note on Tamagawa numbers of tori attached to CM algebras

2022/06/30 by Yasuhiro Oki, Oki, Yasuhiro
Mathematics · #Advanced Combinatorial Mathematics #Advanced Topics in Algebra #Algebraic structures and combinatorial models #FOS: Mathematics #Number Theory (math.NT)

paper · pdf · doi:10.48550/arxiv.2206.15230

openalex publication_date 2022/06/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We prove that any integer power of 2 can be realized as the Tamagawa number of a torus attached to a CM algebra considered by Guo Sheu Yu and Liang Yang Yu. Such a result is obtained by Liang Yang Yu under assuming "a generalized Landau conjecture". The main contribution of this paper is to remove the above assumption.

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