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Determine the Euler characteristic of the surface

$$ M=\left\{(x,y,z); \sqrt{x^2+y^2}=1+z^{2n}, 0< z< 1\right\} $$

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    For $n \in \mathbb{N}$ (including n=0), you just have one cylinder. For non-positive integers, the disjoint union of two cylinders.2010-08-26
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    Sounds like homework...2010-08-26
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    This doesn't look compact to me...2010-08-26

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For any $n\in \mathbb{R}$, your surface is a cylinder, and homotopic to the circle.

(I don't see why Agusti Roig gets the disjoint union of two cylinders)