G. Exoo

activity

20182025

most citedOn Mixed Cages

4 citations · 11 across the 8 of their papers we have counts for

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Showing 2018Show all

3 papers · 1 filter

math.CO2018

The Hadwiger-Nelson problem with two forbidden distances

Geoffrey Exoo, Dan Ismailescu

In 1950 Edward Nelson asked the following simple-sounding question: \emph{How many colors are needed to color the Euclidean plane $E^{2}$ such that no two points distance $1…

math.CO2018

Bounds for the smallest $k$ -chromatic graphs of given girth

Geoffrey Exoo, Jan Goedgebeur

Let $n_{g} (k)$ denote the smallest order of a $k$ -chromatic graph of girth at least $g$ . We consider the problem of determining $n_{g} (k)$ for small values of $k$ and $g$ . After giving…

math.CO2018

The chromatic number of the plane is at least 5 - a new proof

Geoffrey Exoo, Dan Ismailescu

We present an alternate proof of the fact that given any 4-coloring of the plane there exist two points unit distance apart which are identically colored.

The Hadwiger-Nelson problem with two forbidden distances

Bounds for the smallest k-chromatic graphs of given girth

The chromatic number of the plane is at least 5 - a new proof

Bounds for the smallest $k$ -chromatic graphs of given girth