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We define a family of groups that include the mapping class group of a genus g
surface with one boundary component and the integral symplectic group Sp(2g, Z).
We then prove that these groups are finitely generated. These groups, which we call
mapping class groups over graphs, are indexed over labeled simplicial graphs with 2g
vertices. The mapping class group over the graph Γ is defined to be a subgroup of the
automorphism group of the right-angled Artin group AΓ of Γ. We also prove that the
kernel of AutAΓ → AutH1(AΓ) is finitely generated, generalizing a theorem of
Magnus.
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