Class-Preserving Automorphisms of Certain HNN Extensions of Baumslag-Solitar Groups

Abstract

Abstract. We show that, for any non-zero integers λ, µ, ν, ξ, classpreserving automorphisms of the groupare all inner. Hence, by using Grossman's result, the outer automorphism group of G(λ, ±λ, ν, ξ) is residually finite.