In this paper, we show that a matrix algebra LMIp(C) is pseudo-contractible if and only if I is finite. In addition, for each non-empty set I, we show that LMIp(C) is always pseudo-amenable. Amenability, approximate biprojectivity and approximate biflatness of upper triangular algebras with respect to LMIp(C) are discussed here, where 1 ≤ p ≤ 2.
