User Hao S

5 votes

1 answer

423 views

What is the LP gap of vertex cover in planar graphs?

asked Apr 11, 2018 at 15:32

5 votes

0 answers

198 views

"separators" for nonplanar graphs embedded in the plane

asked Mar 21 at 23:30

4 votes

0 answers

144 views

Can the vertices of a planar graph of min degree 3 be covered with edges of average weight ( sum of degrees) at most 14?

asked Aug 15, 2019 at 0:36

4 votes

3 answers

560 views

Can anyone suggest a text on polyhedral theory?

asked Aug 6, 2014 at 18:31

2 votes

1 answer

95 views

Dipping into sets of parallel edges in graph drawings

asked Jul 29 at 17:33

1 vote

1 answer

75 views

Given a vertex $u$ (of bounded degree $k$) and another vertex $v$ in a planar graph, what is the smallest number of "curves"?

asked Jan 17, 2020 at 19:56

1 vote

0 answers

77 views

Is there a variant of the crossing lemma for multigraphs with arbitrary embedding?

asked Mar 24 at 20:34

1 vote

0 answers

97 views

Problem related to crossing number

asked Jun 4 at 17:08

1 vote

0 answers

42 views

What lower bounds are known for pair crossing number and related questions in multigraphs?

asked Jun 21 at 6:59

0 votes

2 answers

348 views

If a graph embedded on a surface is divided by a curve into a right and left that do not intersect can it be embedded on a surface of smaller genus?

asked Nov 15, 2023 at 21:34

0 votes

2 answers

136 views

What are some examples of isotrophic sets?

asked Dec 30, 2014 at 5:48

-1 votes

1 answer

1k views

How to show the square root function of a positive semidefinite matrix is differentiable? [closed]

asked Jan 7, 2015 at 6:00

Stack Exchange Network

12 Questions

What is the LP gap of vertex cover in planar graphs?

"separators" for nonplanar graphs embedded in the plane

Can the vertices of a planar graph of min degree 3 be covered with edges of average weight ( sum of degrees) at most 14?

Can anyone suggest a text on polyhedral theory?

Dipping into sets of parallel edges in graph drawings

Given a vertex $u$ (of bounded degree $k$) and another vertex $v$ in a planar graph, what is the smallest number of "curves"?

Is there a variant of the crossing lemma for multigraphs with arbitrary embedding?

Problem related to crossing number

What lower bounds are known for pair crossing number and related questions in multigraphs?

If a graph embedded on a surface is divided by a curve into a right and left that do not intersect can it be embedded on a surface of smaller genus?

What are some examples of isotrophic sets?

How to show the square root function of a positive semidefinite matrix is differentiable? [closed]