*s-tuple and *n-tuple of Covariant Functors
S. Al-Nofayee *
Department of Mathematics, Taif University, Hawiah 21974, Saudi Arabia.
*Author to whom correspondence should be addressed.
Abstract
A right A-module M is a
-module provided that M is self-small and any exact sequence
0 → N → L → Q → 0,
with L, Q ∈ Stat(M) remains exact after applying the functor HomA(M, -) if and only if N ∈ Stat(M). A right A-module M is called a
-module if it is self-small, (n + 1)-quasi-projective and n-Pres(M) = (n + 1)-Pres(M). In this work we generalize the concepts of
-module and
-modules to the concepts of
-tuple and
-tuple of Contravariant Functors between abelian categories.
Keywords: *s -module, *n -modules, contravariant functor, right adjoint functors