SCAP-subalgebras of Lie algebras
A subalgebra of a finite dimensional Lie algebra is said to be a -subalgebra if there is a chief series of such that for every , we have or . This is analogous to the concept of -subgroup, which has been studied by a number of authors. In this article, we investigate the connection between the structure of a Lie algebra and its -subalgebras and give some sufficient conditions for a Lie algebra to be solvable or supersolvable.