Hypermap operations of finite order
نویسندگان
چکیده
منابع مشابه
Hypermap operations of finite order
Duality and chirality are examples of operations of order 2 on hypermaps. James showed that the groups of all operations on hypermaps and on oriented hypermaps can be identified with the outer automorphism groups Out∆ ∼= PGL2(Z) and Out∆ ∼= GL2(Z) of the groups ∆ = C2 ∗ C2 ∗ C2 and ∆ + = F2. We will consider the elements of finite order in these two groups, and the operations they induce. MSC c...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2010
ISSN: 0012-365X
DOI: 10.1016/j.disc.2009.12.019