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Martin Brandenburg
  • Member for 12 years, 5 months
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  • Berlin, Germany
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All Questions Answers
Score Newest
answer
275
Examples of common false beliefs in mathematics
May 5, 2010
question
101
A proof for $\dim(R[T])=\dim(R)+1$ without prime ideals?
Jun 21, 2014
question
90
$A$ is isomorphic to $A \oplus \mathbb{Z}^2$, but not to $A \oplus \mathbb{Z}$
Sep 12, 2015
question
81
When is $A$ isomorphic to $A^3$?
Dec 30, 2009
question
74
$R$ is isomorphic to $R[X,Y]$, but not to $R[X]$
Dec 11, 2015
question
72
Rigidity of the category of schemes
Feb 28, 2011
answer
71
What are the reasons for considering rings without identity?
Apr 26, 2010
answer
66
Example of an unnatural isomorphism
Aug 14, 2013
question
65
explicit big linearly independent sets
May 1, 2010
answer
57
Counterexamples in algebra?
Jun 22, 2010
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788
A proof for $\dim(R[T])=\dim(R)+1$ without prime ideals?
168
Nice examples of groups which are not obviously groups
143
If $AB = I$ then $BA = I$
96
Ring structure on the Galois group of a finite field
67
Geometric intuition for the tensor product of vector spaces

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