On the endomorphisms and derivations of some Leibniz algebras

We study the endomorphisms and derivations of an infinite-dimensional cyclic Leibniz algebra. Among others it was found that if [Formula: see text] is a cyclic infinite-dimensional Leibniz algebra over a field [Formula: see text], then the group of all automorphisms of [Formula: see text] is isomorphic to a multiplicative group of the field [Formula: see text]. The description of an algebra of derivations of a cyclic infinite-dimensional Leibniz algebra has been obtained.