How many colors does it take to color a
map so no two regions have the
same color?
Four Color Theorem
( Guthrie’s Problem)
1… 2… 3… 4…!
A little history…
Francis Guthrie,
in 1852 was
the first to put the four
color
theorem into words.
While coloring a map of
counties of England
He noticed that only four
colors were needed.
Defining the Four Color
Theorem
Any map can in a plane can be colored
with only four colors so that now
regions having a common boundary
have the same color.
Those regions that have only a point in
common are not considered to have
shared boundaries.
The four color
theorem is a
mathematical
brainteaser that
can be appreciated
by nonmathematicians
as well as
mathematicians.
Computer Controversy
In 1976 , the conjecture was
apparently proven by
Wolfgang Haken and
Kenneth Appel with the aid of
a computer.
The proof of the four color
theorem is a doorway to
some interesting questions
about the role of human
minds and computing
machines in mathematics.
Consider the coloring of
geographical maps, is the
problem basically a
topological problem?
Yes, in that it depends only on the
connectives between the countries, not
on their specific shapes, sizes, or
positions.
Flash! -Mathematical
Breakthrough!
In December 2004, Dr. George
Gonthier
removed last doubts about
the proof of the Four Color Theorem.
Contributors
Wendy Cozart
Dr. Geo. Gonthier
Nancy Lutz
Thelma Mayes
August F. Mobius
Kristen Ochs
M. Lynne Ryan
ToniAnne Tillotson