The Reduction of an RG–Lattice Modulo pn
1990 ◽
Vol 42
(2)
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pp. 342-364
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Keyword(s):
We define the cover of an RG-module V to consist of an RG lattice Ṽ and a homomorphism π : Ṽ→ V such that π induces an isomorphism on Ext*RG(M, —) for any RG-lattice M. Here G is a finite group and, for simplicity in this introduction, R is a complete discrete valuation ring of characteristic zero with prime element p and perfect valuation class field. Let pn(G) be the highest power of p that divides |G| and, given an RG-lattice M, let pn(M) be the smallest power of p such that pn(M) idM : M→M factors through a projective lattice: n(M)≦n(G).
2011 ◽
Vol 148
(1)
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pp. 227-268
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2019 ◽
Vol 2019
(754)
◽
pp. 1-15
1978 ◽
Vol s2-18
(3)
◽
pp. 464-471
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Keyword(s):
1984 ◽
Vol 35
(2)
◽
pp. 131-146
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