3-Engel Lie ring

Definition
A Lie ring $$L$$ is termed a 3-Engel Lie ring if it satisfies the following:

$$[x,[x,[x,y]]] = 0 \ \forall \ x,y \in L$$

Facts

 * 3-Engel and 2-torsion-free implies 2-local class three for Lie rings
 * 3-Engel and (2,5)-torsion-free implies class six for Lie rings