More about Homological Properties of Precrossed Modules
نویسنده
چکیده
Homology groups modulo q of a precrossed P-module in any dimensions are deened in terms of nonabelian derived functors, where q is a nonnegative integer. The Hopf formula is proved for the second ho-mology group modulo q of a precrossed P-module which shows that for q = 0 our deenition is a natural extension of Conduch e and El-lis' deenition CE]. Some other properties of homologies of precrossed P-modules are investigated.
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