Graham's Number
The smallest dimension of a Hypercube such that if the lines joining all pairs of corners are two-colored, aPlanar Complete Graph 
of one color will be forced. That an answer exists was proved byR. L. Graham and B. L. Rothschild. The actual answer is believed to be 6, but the best bound proved is
where
is stacked Arrow Notation. It is less than 
, where Chained Arrow Notation hasbeen used.See also Arrow Notation, Chained Arrow Notation, Skewes Number
References
Conway, J. H. and Guy, R. K. The Book of Numbers. New York: Springer-Verlag, pp. 61-62, 1996. Gardner, M. ``Mathematical Games.'' Sci. Amer. 237, 18-28, Nov. 1977.
- Determinant Expansion by Minors
- Determinant (Knot)
- Determinant Theorem
- Developable Surface
- Deviation
- Devil on Two Sticks
- Devil's Curve
- Devil's Staircase
- Diabolical Cube
- Diabolical Square
- Diabolo
- Diacaustic
- Diagonalization
- Diagonal Matrix
- Diagonal Metric
- Diagonal (Polygon)
- Diagonal (Polyhedron)
- Diagonal Ramsey Number
- Diagonal Slash
- Diagonal (Solidus)
- Diagonals Problem
- Diagram
- Diameter
- Diameter (General)
- Diameter (Graph)