Automorphism Groups of Compact Planar Klein Surfaces.
Automorphism Groups of Designs.
Automorphism invariants for semigroups.
Automorphisms and enumeration of switching classes of tournaments.
Automorphisms of completely primary finite rings of characteristic p
A completely primary ring is a ring R with identity 1 ≠ 0 whose subset of zero-divisors forms the unique maximal ideal . We determine the structure of the group of automorphisms Aut(R) of a completely primary finite ring R of characteristic p, such that if is the Jacobson radical of R, then ³ = (0), ² ≠ (0), the annihilator of coincides with ² and , the finite field of elements, for any prime p and any positive integer r.
Automorphisms of models of bounded arithmetic
We establish the following model-theoretic characterization of the fragment IΔ₀ + Exp + BΣ₁ of Peano arithmetic in terms of fixed points of automorphisms of models of bounded arithmetic (the fragment IΔ₀ of Peano arithmetic with induction limited to Δ₀-formulae). Theorem A. The following two conditions are equivalent for a countable model of the language of arithmetic: (a) satisfies IΔ₀ + BΣ₁ + Exp; (b) for some nontrivial automorphism j of an end extension of that satisfies IΔ₀. Here is the...
Automorphisms of regular wreath product -groups.
Autormorphism groups of countable highly homogeneous partially ordererd sets.
Avoiding maximal parabolic subgroups of .