Lie algebras MOC Triangular Lie algebra Let be a Lie algebra over . A triangular decomposition of is a triple of subalgebras such that where is abelian and .1 lie A Lie algebra with such a decomposition is called triangular. This may be viewed as a generalization of a Heisenberg algebra. Properties Triangular module Contravariant form on a triangular module Examples Special linear Lie algebra tidy | en | sembr Footnotes 1988. Vertex operator algebras and the Monster, §1.8, p. 26 ↩