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Register a new userA finitely generated group that does not satisfy the generalized Burghelea Conjecture
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We construct a finitely generated group that does not satisfy the generalized Burghelea conjecture.
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We give an elementary proof of the well-known fact that the third cohomology group H^3(G, M) of a group G with coefficients in an abelian G-module M is in bijection to the set Ext^2(G, M) of equivalence classes of crossed module extensions of G with M.
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