We prove that sequentially Cohen-Macaulay rings in positive characteristic, as well as sequentially Cohen-Macaulay Stanley-Reisner rings in any characteristic, have trivial Lyubeznik table. Some other configurations of Lyubeznik tables are also provided depending on the deficiency modules of the ring.

We prove a Cohen-Macaulay version of result by Avramov-Golod and Frankild-J{\o}rgensen about Gorenstein rings, showing that if noetherian ring $A$ is Cohen-Macaulay, $a_1,\dots,a_n$ any sequence elements in $A$, then the Koszul complex $K(A;a_1,\dots,a_n)$ DG-ring. further generalize this result, it also holds for commutative DG-rings. In process proving this, we develop new technique to study ...

One of the first remarkable results in representation theory artin algebras, due to Auslander and Ringel-Tachikawa, is characterisation when an algebra representation-finite. In this paper, we investigate aspects representation-finiteness general context exact categories sense Quillen. framework, introduce “big objects” prove Auslander-type “splitting-big-objects” theorem. Our approach generali...