In this paper, we show that a matrix algebra LMp I (C) posses a central approximate identity if and only if I is finite. As an application, LMp I (C) is pseudo- contractible if and only if I is finite. Also, for each non-empty set I, we show that LMp I (C) is always pseudo-amenable. Amenability, approximate biprojectivity and ap- proximate biflatness of upper triangular algebra with respect to LMp I (C) are discussed here, where 1 p 2.