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Page "Four color theorem" ¶ 13
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graph and is
In some neighborhood in the f-plane of any ordinary point of the graph, the function f is a single-valued, continuous function.
The graph of f has at least one component whose support is the entire interval Aj.
We have shown that the graph of F contains at least one component whose inverse is the entire interval {0,T}, and whose multiplicity is odd.
Figure 2 is a graph of the mean achievement scores of each group.
If the force required to remove the coatings is plotted against film thickness, a graph as illustrated schematically in Fig. 5 may characteristically result.
* In graph theory an automorphism of a graph is a permutation of the nodes that preserves edges and non-edges.
The b value compresses the graph of the function horizontally if greater than 1 and stretches the function horizontally if less than 1, and like a, reflects the function in the y-axis when it is negative.
The graph of R ( x, y ) is changed by standard transformations as follows:
Although the description sitting-on ( graph 1 ) is more abstract than the graphic image of a cat sitting on a mat ( picture 1 ), the delineation of abstract things from concrete things is somewhat ambiguous ; this ambiguity or vagueness is characteristic of abstraction.
Asymptotes convey information about the behavior of curves in the large, and determining the asymptotes of a function is an important step in sketching its graph.
The line x = a is a vertical asymptote of the graph of the function
It is impossible for the graph of a function to intersect a vertical asymptote ( or a vertical line in general ) in more than one point.
While the numerical difference between the decimal and binary interpretations is relatively small for the prefixes kilo and mega, it grows to over 20 % for prefix yotta, illustrated in the linear-log graph ( at right ) of difference versus storage size.
Binary relations are used in many branches of mathematics to model concepts like " is greater than ", " is equal to ", and " divides " in arithmetic, " is congruent to " in geometry, " is adjacent to " in graph theory, " is orthogonal to " in linear algebra and many more.
The sets X and Y are called the domain ( or the set of departure ) and codomain ( or the set of destination ), respectively, of the relation, and G is called its graph.
Some mathematicians, especially in set theory, do not consider the sets and to be part of the relation, and therefore define a binary relation as being a subset of x, that is, just the graph.
* A Gaussian function, a specific kind of function whose graph is a bell-shaped curve

graph and planar
In graph theory, the term fullerene refers to any 3-regular, planar graph with all faces of size 5 or 6 ( including the external face ).
Conversely any planar graph can be formed from a map in this way.
In graph-theoretic terminology, the four-color theorem states that the vertices of every planar graph can be colored with at most four colors so that no two adjacent vertices receive the same color, or for short, " every planar graph is four-colorable " (; ).
First, if planar regions separated by the graph are not triangulated, i. e. do not have exactly three edges in their boundaries, we can add edges without introducing new vertices in order to make every region triangular, including the unbounded outer region.
So it suffices to prove the four color theorem for triangulated graphs to prove it for all planar graphs, and without loss of generality we assume the graph is triangulated.
The intuitive idea underlying discharging is to consider the planar graph as an electrical network.
To prove this, one can combine a proof of the theorem for finite planar graphs with the De Bruijn – Erdős theorem stating that, if every finite subgraph of an infinite graph is k-colorable, then the whole graph is also k-colorable.
For a planar graph, the crossing number is zero by definition.
* A graph is planar if it contains as a minor neither the complete bipartite graph ( See the Three-cottage problem ) nor the complete graph.
The minimum spanning tree of a planar graph.
Every tree with only countably many vertices is a planar graph.
In mathematics, Tait's conjecture states that " Every 3-connected planar cubic graph has a Hamiltonian cycle ( along the edges ) through all its vertices ".
In a Hamiltonian cubic planar graph, such an edge coloring is easy to find: use two colors alternately on the cycle, and a third color for all remaining edges.
Alternatively, a 4-coloring of the faces of a Hamiltonian cubic planar graph may be constructed directly, using two colors for the faces inside the cycle and two more colors for the faces outside.
The resulting Tutte graph is 3-connected and planar, so by Steinitz ' theorem it is the graph of a polyhedron.
In more formal graph-theoretic terms, the problem asks whether the complete bipartite graph K < sub > 3, 3 </ sub > is planar.

graph and important
Several fields of discrete mathematics, particularly theoretical computer science, graph theory, and combinatorics, are important in addressing the challenging bioinformatics problems associated with understanding the tree of life.
Another important factor of common development of graph theory and topology came from the use of the techniques of modern algebra.
Again, some important graph properties are hereditary with respect to induced subgraphs, which means that a graph has a property if and only if all induced subgraphs also have it.
He made important discoveries in fields as diverse as infinitesimal calculus and graph theory.
An important subclass are the local search methods, that view the elements of the search space as the vertices of a graph, with edges defined by a set of heuristics applicable to the case ; and scan the space by moving from item to item along the edges, for example according to the steepest descent or best-first criterion, or in a stochastic search.
An important and extensively studied subclass are the graph algorithms, in particular graph traversal algorithms, for finding specific sub-structures in a given graph — such as subgraphs, paths, circuits, and so on.
It is important to note that this graph does not show the instantaneous voltage profile along the transmission line.
Two important characterizations of planar graphs, Kuratowski's theorem that the planar graphs are exactly the graphs that contain neither K < sub > 3, 3 </ sub > nor the complete graph K < sub > 5 </ sub > as a subdivision, and Wagner's theorem that the planar graphs are exactly the graphs that contain neither K < sub > 3, 3 </ sub > nor K < sub > 5 </ sub > as a minor, encompass this result.
One of the more important uses of text in a graph is in the title.
Lookahead is an important component of combinatorial search which specifies, roughly, how deeply the graph representing the problem is explored.
: " When calculators can do multidigit long division in a microsecond, graph complicated functions at the push of a button, and instantaneously calculate derivatives and integrals, serious questions arise about what is important in the mathematics curriculum and what it means to learn mathematics.
An important point is that the fractional derivative at a point x is a local property only when a is an integer ; in non-integer cases we cannot say that the fractional derivative at x of a function f depends only on the graph of f very near x, in the way that integer-power derivatives certainly do.
The number of connected components is an important topological invariant of a graph.
Using Fibonacci heaps for priority queues improves the asymptotic running time of important algorithms, such as Dijkstra's algorithm for computing the shortest path between two nodes in a graph.
Don Woods was doing doctoral research in graph algorithms, and he designed this maze as ( almost ) a complete graph, with two exceptions important to game play.
Finally, root systems are important for their own sake, as in graph theory in the study of eigenvalues.
An important example is a function whose domain is a closed ( and bounded ) interval of real numbers ( see the graph above ).
However, these problems also differ in several important ways: for instance, in EDA, area minimization and signal length are more important than aesthetics, and the routing problem in EDA may have more than two terminals per net while the analogous problem in graph drawing generally only involves pairs of vertices for each edge.

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