￿n automorphism groups of affine surfaces Sergei Kovalenko, Alexander Perepechko, Mikhail Zaidenberg

Free periodic groups, Burnside groups, group automorphisms, Fibonacci morphism, Fibonacci sequence, Fibonacci word, golden ratio.. 1 Faculty of Mathematics and Mechanics, Yerevan

- We prove that a finite group is (isomorphic to) an automorphism group of a toroidal hypermap if and only if it is abelian of rank at most two or it can be decomposed as the

T HEOREM. Let f be an automorphism of the finite extension G of a soluble FAR group. For i) it suffices to assume only that G is a group with finite Hirsch number (even in a

Rendiconti del Seminario Matematico della Università di Padova, tome 94 (1995),

study of certain algebraic objects which appear in algebraic geometry - subschemes of a given scheme, vector bundles on a given variety, all curves.. of fixed genus,

be proved by the methods of [3]. There we proved only the topological equivalence of the action to the orthogonal one given by r, and left the remainder of the proof

THEOREM 2.5: The quotient G/Rad G can be embedded as a direct sum of a fznite number of linear groups over locally finite fields. PROOF: The isomorphism between

is finitely generated, abelian-by-finite and centralized by a finite index subgroup of Out (Γ). The case of a general polycyclic-by-finite group. — In this subsection, we ex- plain