Hao S's user avatar
Hao S's user avatar
Hao S's user avatar
Hao S
  • Member for 9 years, 7 months
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5 votes
1 answer
393 views

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

4 votes
0 answers
124 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?

4 votes
3 answers
530 views

Can anyone suggest a text on polyhedral theory?

2 votes
0 answers
77 views

"separators" for nonplanar graphs embedded in the plane

1 vote
1 answer
73 views

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

0 votes
0 answers
27 views

What is known about "overlapping" models/minors of graphs

0 votes
2 answers
316 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?

0 votes
0 answers
24 views

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

0 votes
2 answers
134 views

What are some examples of isotrophic sets?

-1 votes
1 answer
1k views

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