2025/03/28 by Fu, Changjian, Liang, Zhanhong
#13F60 #FOS: Mathematics #Rings and Algebras (math.RA)
paper · doi:10.48550/arxiv.2503.22101
We introduce a pseudo ℕ-grading on the cluster auotmorphism group Aut(A) with respect to an initial seed of A, which consists of a family of subsets \Gi\i∈ ℕ of Aut(A) such that Aut(A)=\bigcupi∈ ℕGi and Gk⋅ Gl⊂ \bigcupi=0k+lGi. We prove that Aut(A) is generated by G0∪ G1, leading to an elementary approach for calculating cluster automorphism groups of certain cluster algebras. As an application, we completely determined the cluster automorphism groups of cluster algebras of rank 3 with indecomposable exchange matrices.