Search Results for ""

Given n matches (i.e., rigid unit line segments), find the number of topologically distinct planar arrangements which can be made (Gardner 1991). In this problem, two matches ...

To color any map on the sphere or the plane requires at most six-colors. This number can easily be reduced to five, and the four-color theorem demonstrates that the necessary ...

A tree to whose nodes and/or edges labels (usually number) are assigned. The word "weight" also has a more specific meaning when applied to trees, namely the weight of a tree ...

Multiple edges are two or more edges connecting the same two vertices within a multigraph. Multiple edges of degree d_(ij) between vertex i and vertex j correspond to an ...

The 600-cell is the finite regular four-dimensional polytope with Schläfli symbol {3,3,5}. It is also known as the hypericosahedron or hexacosichoron. It is composed of 600 ...

A closed trail is called a circuit when it is specified in cyclic order but no first vertex is explicitly identified.

A Ramsey number of the form R(k,k;2).

Edge splitting is the reverse of edge contraction.

An elegant algorithm for constructing an Eulerian cycle (Skiena 1990, p. 193).

The problem of deciding if four colors are sufficient to color any map on a plane or sphere.