In mathematics, the ith Bass number of a module M over a local ring R with residue field k is the k-dimension of
More generally the Bass number
of a module M over a ring R at a prime ideal p is the Bass number of the localization of M for the localization of R (with respect to the prime p).
The Bass numbers describe the minimal injective resolution of a finitely-generated module M over a Noetherian ring: for each prime ideal p there is a corresponding indecomposable injective module, and the number of times this occurs in the ith term of a minimal resolution of M is the Bass number
This commutative algebra-related article is a stub.