Matchstick Graph
A Planar Graph whose Edges are all unit line segments. The minimal number of Edges for matchstick graphsof various degrees are given in the table below. The minimal degree 1 matchstick graph is a single Edge, and theminimal degree 2 graph is an Equilateral Triangle.
 |  |  |
| 1 | 1 | 2 |
| 2 | 3 | 3 |
| 3 | 12 | 8 |
| 4 |  42 |
- W2-Constant
- Wada Basin
- Walk
- Wallace-Bolyai-Gerwein Theorem
- Wallace-Simson Line
- Wallis Cosine Formula
- Wallis Formula
- Wallis's Conical Edge
- Wallis Sieve
- Wallis Sine Formula
- Wallis's Problem
- Wallpaper Groups
- Walsh Function
- Walsh Index
- Wang's Conjecture
- Ward's Primality Test
- Waring Formula
- Waring's Conjecture
- Waring's Prime Conjecture
- Waring's Problem
- Waring's Sum Conjecture
- Waring's Theorem
- Watchman Theorem
- Watson-Nicholson Formula
- Watson Quintuple Product Identity