The fundamental group of a torus is Z[tex]*[/tex]Z,then the fundamental group of a punctured torus is Z[tex]*[/tex]Z[tex]*[/tex]Z.(adsbygoogle = window.adsbygoogle || []).push({});

But I've ever done a problem,it said a punctured torus can be continuously deformed into two cylinders glued to a square patch.Really?

If that is right,then the fundamental group of punctured torus is Z[tex]*[/tex]Z.

Which is right?Need help

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# What's the fundamental group of a punctured torus?

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