Derivations of the Lie algebra of strictly upper triangular matrices over a commutative ring

Abstract Let R be an arbitrary commutative ring with identity, gl( n ,  R ) the general linear Lie algebra consisting of all n  ×  n matrices over R , N ( n ,  R ) the subalgebra of gl( n ,  R ) consisting of all strictly upper triangular ones. In this paper, we give an explicit description of any derivations of N ( n ,  R ).