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Wood, David R.
Forcing a $K_6$-minor ★★
Author(s): Barát ; Joret; Wood
Conjecture Every graph with minimum degree at least 7 contains a
-minor.
-minor. Conjecture Every 7-connected graph contains a
-minor.
-minor. Keywords: connectivity; graph minors
Point sets with no empty pentagon ★
Author(s): Wood
Problem Classify the point sets with no empty pentagon.
Keywords: combinatorial geometry; visibility graph
Number of Cliques in Minor-Closed Classes ★★
Author(s): Wood
Question Is there a constant
such that every
-vertex
-minor-free graph has at most
cliques?
such that every
-vertex
-minor-free graph has at most
cliques? Compatible Matching Conjecture ★★
Author(s): Wood
For an even set
of points in the plane, a perfect matching of
is a collection of nonintersecting segments such that every point of
is an end of exactly one of the segments.
Conjecture Let
be a set of points in the plane in general position such that
is divisible by 4. Then for every perfect matching
of
there is another perfect matching,
, of
such that no segment of
crosses a segment of
.
be a set of points in the plane in general position such that
is divisible by 4. Then for every perfect matching
of
there is another perfect matching,
, of
such that no segment of
crosses a segment of
. Keywords: geometric graphs; matchings
Big Line or Big Clique in Planar Point Sets ★★
Let
be a set of points in the plane. Two points
and
in
are visible with respect to
if the line segment between
and
contains no other point in
.
Conjecture For all integers
there is an integer
such that every set of at least
points in the plane contains at least
collinear points or
pairwise visible points.
there is an integer
such that every set of at least
points in the plane contains at least
collinear points or
pairwise visible points. Keywords: Discrete Geometry; Geometric Ramsey Theory
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