Definition 3 A universal cover of a topological space \(X\) is a covering space \(\tilde{X}\) of \(X\) that is simply connected, meaning that it has no nontrivial loops. The universal cover is unique up to homeomorphism and serves as a “universal” object in the category of covering spaces of \(X\).
index = max(0, index - 1)
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Студенты нашли останки викингов в яме для наказаний14:52