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Bjørn Kjos-Hanssen

University of Hawaii

http://math.hawaii.edu/wordpress/bjoern/

  • Moderator at Theoretical Computer Science

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Top Questions
20 votes

Weighted Hamming distance

co.combinatorics randomness asked Nov 2, 2010 at 5:06
cstheory.stackexchange.com

20 votes

Models of ZFC and the Borel hierarchy

lo.logic set-theory asked Apr 8, 2017 at 7:29
mathoverflow.net

20 votes

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

at.algebraic-topology finite-groups geometric-group-theory topological-graph-theory cayley-graphs asked Jul 3, 2018 at 1:36
mathoverflow.net

18 votes

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

set-theory universal-algebra boolean-algebras asked Feb 21, 2014 at 17:51
mathoverflow.net

14 votes

Finding symbols in Lean

lean tutorials asked Feb 9, 2022 at 22:43
proofassistants.stackexchange.com

14 votes

Unpublished result of Rosser in Sieve Methods book

nt.number-theory reference-request prime-numbers sieve-theory asked Feb 16, 2022 at 0:05
mathoverflow.net

13 votes

Is the nearest walk to Brownian motion uniform?

pr.probability asked Sep 12, 2010 at 6:20
mathoverflow.net

12 votes

Example of something that’s different for generic and random oracles?

cc.complexity-theory complexity-classes asked Sep 11, 2017 at 1:50
cstheory.stackexchange.com

12 votes

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

reference-request pr.probability mg.metric-geometry real-analysis ho.history-overview asked Jan 6, 2015 at 2:06
mathoverflow.net

11 votes

Is there an official recommendation for editors to input Lean unicode characters?

lean recommendations asked Feb 10, 2022 at 0:37
proofassistants.stackexchange.com

1 2 3 4

Top Answers
72
Do you need to read a whole article before citing it?
academia.stackexchange.com

57
Is there a measure zero set which isn't meagre?
mathoverflow.net

51
When mentioning the author of a journal I am using in my Literature Review, should I mention author's credentials?
academia.stackexchange.com

47
Do any two spanning trees of a simple graph always have some common edges?
cs.stackexchange.com

45
Intuition for random variable being $\sigma$-algebra measurable?
math.stackexchange.com

44
Suggestions for good notation
mathoverflow.net

37
If all balls at $x$ and $y$ are isometric is there an isometry sending $x$ to $y$?
mathoverflow.net

33
Are there any proofs the undecidability of the halting problem that does not depend on self-referencing or diagonalization ?
cstheory.stackexchange.com

33
Examples of Mathematical Papers that Contain a Kind of Research Report
mathoverflow.net

32
On sentences true in all finite groups
mathoverflow.net

26
What is the reverse mathematical strength of the fundamental theorem of algebra?
mathoverflow.net

26
Should one avoid using the phrase "note that" in math writings?
academia.stackexchange.com

25
Languages beyond enumerable
mathoverflow.net

22
Is there a known Turing machine which halts if and only if the Collatz conjecture has a counterexample?
mathoverflow.net

21
History of powers beyond squares and cubes
mathoverflow.net

21
How and why did the top journals become top journals?
academia.stackexchange.com

21
For which Millennium Problems does undecidable -> true?
mathoverflow.net

21
Question arising from Voevodsky's talk on inconsistency
mathoverflow.net

20
Are countable dense subspaces of $\mathbb{R}^n$ homeomorphic to ${\mathbb Q}^n$?
mathoverflow.net

20
Why is the Gaussian so pervasive in mathematics?
mathoverflow.net

18
In what sense is GCD an extension of boolean OR?
mathoverflow.net

18
Is there algorithmic mathematical analysis?
cstheory.stackexchange.com

18
Add unpublished but widely cited paper to CV?
academia.stackexchange.com

18
Why is weak Kőnig's lemma weaker than Kőnig's lemma?
mathoverflow.net

18
Is it appropriate/safe to ask for help on major theorem proof of my paper online?
academia.stackexchange.com

18
Meaning of completeness of a statistic?
stats.stackexchange.com

17
Why is this new result such a big deal?
mathoverflow.net

17
Is Turing degree actually useful in real life?
mathoverflow.net

17
Probably true, but provably unprovable
mathoverflow.net

16
Intuition of law of iterated logarithm?
mathoverflow.net

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