# Co-prolongations of a group extension

Document Type: Research Paper

Authors

1 Hanoi National University of Education

2 National Economics University

3 Hanoi University of Science and Technology

Abstract

The aim of this paper is to study co-prolongations‎ ‎of central extensions‎. ‎We construct the obstruction theory for‎ ‎co-prolongations‎ ‎and classify the equivalence classes of these by kernels of homomorphisms‎ ‎between 2-dimensional cohomology groups of groups‎.

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### References

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