Derivations of the Lie algebra of strictly block upper triangular   matrices
  Let ${\mathcal N}$ be the Lie algebra of all $n\times n$ strictly block upper triangular matrices over a field ${\mathbb F}$ relative to a given partition. In this paper, we give an explicit description of all derivations of ${\mathcal N}$. 
Prakash Ghimire, Huajun Huang
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