The Schreier Technique for Subalgebras of a Free Lie Algebra
The Schreier Technique for Subalgebras of a Free Lie Algebra
Abstract In group theory Schreier's technique provides a basis for a subgroup of a free group. In this paper an analogue is developed for free Lie algebras. It hinges on the idea of cutting a Hall set into two parts. Using it, we show that proper subalgebras of finite codimension …