1.10 Auslander-Buchsbaum Formula
BH 1.3.4
Proof
Uses
* def of associated primes
* a fact about associated primes giving and embedding
* some facts about commutative squares (maybe already in lean?)
* tensor products of modules
* Nakayama (a corollary, like Atiyah-MacDonald 2.8 but uses maps, might just follow from AM 2.8)
BH 1.3.5
Proof
This uses
* BH 1.1.5
* The "tor" characterization of projective dimension
depth + projdim = depth
Proof