# Growth in the minimal injective resolution of a local ring

@article{Christensen2010GrowthIT, title={Growth in the minimal injective resolution of a local ring}, author={Lars Winther Christensen and Janet Striuli and Oana Veliche}, journal={Journal of the London Mathematical Society}, year={2010}, volume={81} }

Let R be a commutative noetherian local ring with residue field k and assume that it is not Gorenstein. In the minimal injective resolution of R, the injective envelope E of the residue field appears as a summand in every degree starting from the depth of R. The number of copies of E in degree i equals the k‐vector space dimension of the cohomology module ExtiR(k, R). These dimensions, known as Bass numbers, form an infinite sequence of invariants of R about which little is known. We prove that…

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