iv : 0 90 3 . 45 15 v 1 [ m at h . R A ] 2 6 M ar 2 00 9 The Auslander - Type Condition of Triangular Matrix Rings ∗ †
نویسندگان
چکیده
Let R be a left and right Noetherian ring and n, k any non-negative integers. R is said to satisfy the Auslander-type condition Gn(k) if the right flat dimension of the (i+1)-st term in a minimal injective resolution of RR is at most i+ k for any 0 ≤ i ≤ n− 1. In this paper, we prove that R is Gn(k) if and only if so is a lower triangular matrix ring of any degree t over R.
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