Bjørn Kjos-Hanssen's user avatar
Bjørn Kjos-Hanssen's user avatar
Bjørn Kjos-Hanssen's user avatar
Bjørn Kjos-Hanssen
  • Member for 14 years
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20 votes
1 answer
658 views

Models of ZFC and the Borel hierarchy

20 votes
4 answers
2k views

Cayley graph of $A_5$ with generators $(1,2,3,4,5),(1,4,3,2,5)$

18 votes
4 answers
2k views

Complete Boolean algebra not isomorphic to a $\sigma$-algebra

14 votes
1 answer
401 views

Unpublished result of Rosser in Sieve Methods book

13 votes
1 answer
649 views

Is the nearest walk to Brownian motion uniform?

11 votes
1 answer
323 views

Unique words in dihedral groups

11 votes
1 answer
688 views

History of the Jaccard distance $d(A,B) = \mathbb P(\overline A\cup\overline B\mid A\cup B)$

11 votes
2 answers
587 views

Homeomorphisms and "mod finite"

10 votes
6 answers
2k views

Math research in the app store [closed]

10 votes
2 answers
1k views

$\aleph$ looks like $\mathbb N$?

9 votes
4 answers
2k views

Axiom of Infinity needed in Cantor-Bernstein?

9 votes
0 answers
2k views

Weighted Hamming distance

9 votes
2 answers
381 views

A cubefree-preserving morphism from 5 to 2?

9 votes
1 answer
388 views

VC dimension of Borel sets [duplicate]

8 votes
1 answer
251 views

Automorphisms of power set lattice mod finite

8 votes
1 answer
473 views

VC dimension of standard topology on the reals

8 votes
1 answer
249 views

Characterizing surface area

7 votes
1 answer
424 views

Which monoids have a faithful irreducible representation?

6 votes
1 answer
285 views

Group action with unique word

6 votes
5 answers
1k views

Fractals of dimension zero

6 votes
0 answers
199 views

Elementary function relative to erf

6 votes
1 answer
287 views

A group, neither amenable, nor having a subgroup that looks like $F_2$ up to level $n$?

6 votes
1 answer
403 views

An eventually different function adding no Solovay real nor dominating function?

6 votes
1 answer
349 views

Number of partitions whose blocks form arithmetic progressions

5 votes
2 answers
267 views

Smooth convex extensibility of combination of two line segments

5 votes
1 answer
566 views

Quantum probability experiment?

5 votes
0 answers
308 views

Is the nearest walk to Brownian motion approximately uniform?

5 votes
0 answers
149 views

Linear diophantine quasivariety having a unique solution

4 votes
1 answer
299 views

Strings with no long runs from proper subalphabets

4 votes
0 answers
212 views

Equations in finite subgroups of unitary groups