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Mathematics
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Rolf Hoyer

Apparently, this user prefers to keep an air of mystery about them.

365
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  • Member for 4 years
  • 990 profile views
  • Last seen 1 hour ago

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Posts 78
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Top Posts (365) All Questions Answers | Votes Newest

60 $\exists$ a non-compact space in which every proper open subset is compact? Dec 5 '17
33 Only 12 polynomials exist with given properties Apr 18 '15
17 If $\lim_{x\to0} f(x)+g(x)$ and $\lim_{x\to0} f(x)g(x)$ exist simultaneously, are there any $f(x)$ and $g(x)$ that do not have limit Apr 4 '15
15 How to Determine a Power Series Represents an Exponential Function Mar 30 '17
14 $n^2+np$ is a perfect square Mar 30 '17
13 Find the sum of the infinite series $\sum n(n+1)/n!$ May 17 '16
13 Is $4$ the only power of $2$ with a ternary representation consisting of only odd digits? Apr 14 '15
11 homotopic maps? May 8 '15
11 showing an inequality not using stirling formula Aug 14 '15
10 Galois group of $x^4-2$ Apr 12 '15
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