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Bib-lost
  • Member for 6 years, 8 months
  • Last seen this week
  • Antwerp, Belgium
47 votes
11 answers
4k views

Deep theorem with trivial proof [closed]

  • 4,478
18 votes
1 answer
2k views

Upper triangular matrices $B$ that commute with every upper triangular matrix commuting with $A$

  • 181
12 votes
1 answer
365 views

If $R[x]$ and $R[[x]]$ are isomorphic, then are they isomorphic to $R$ as well? [duplicate]

9 votes
2 answers
1k views

Prove that function has only one maximum

  • 211
8 votes
1 answer
2k views

Finitely many prime ideals $\Rightarrow$ cartesian product of local rings

  • 11.1k
8 votes
1 answer
235 views

Analytical proof for the convergence of a sequence

  • 561
8 votes
0 answers
63 views

To get all open sets in $\mathbb{R}^n$ with a unique polynomial

5 votes
0 answers
112 views

What research has been done on applying game theory to Smart Grid software agents that both cooperate and compete?

  • 5,413
5 votes
1 answer
493 views

What is a good book on general octonion algebras and the Cayley-Dickson construction?

  • 3,219
4 votes
2 answers
2k views

Second order ODE, first derivative missing

4 votes
1 answer
84 views

Predicting next headache

  • 1,342
3 votes
0 answers
55 views

Historical use of k in proof by induction

3 votes
2 answers
82 views

Enough differences of powers of natural numbers equals a constant

3 votes
1 answer
160 views

If eigenvectors of a matrix are orthogonal, does that imply anything about the matrix (normal, hermitian, etc)?

  • 1,459
2 votes
1 answer
80 views

Worthwhile freshman-level definite-integrals-"proper"

0 votes
2 answers
435 views

Is $f(z) = |z^2 - z|$ nowhere analytic?

  • 333