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arXiv · 0804.3581

A colimit of classifying spaces

Graham Ellis·Roman Mikhailov
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Abstract

We recall a group-theoretic description of the first non-vanishing homotopy group of a certain (n+1)-ad of spaces and show how it yields several formulae for homotopy and homology groups of specific spaces. In particular we obtain an alternative proof of J. Wu's group-theoretic description of the homotopy groups of a 2-sphere.

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Graham Ellis, Roman Mikhailov. 2008-04-22. A colimit of classifying spaces. https://arxiv.org/abs/0804.3581

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