Stability of strongly Gorenstein flat modules

Abstract

A left $R$-module $M$ is called two-degree Ding projective if there exists an exact sequence $...⟶D_1⟶D_0⟶D_{-1}⟶D_{-2}⟶...$ of Ding projective left $R$-modules such that $M\cong \ker (D_0⟶D_{-1})$ and $\Hom_{R} (-, F)$ leaves the sequence exact for any flat (or Gorenstein flat) left $R$-module $F$. In this paper, we show that the two-degree Ding projective modules are nothing more than the Ding projective modules.

7 pages