This number is the smallest composite Motzkin number, and a theorem based on this number was proven in 1976 by Wolfgang Haken and Kenneth Appel. This is the smallest number of elements in a non-cyclic group, and a tesseract, 
This number is the smallest composite Motzkin number, and a theorem based on this number was proven in 1976 by Wolfgang Haken and Kenneth Appel. This is the smallest number of elements in a non-cyclic group, and a tesseract, or hypercube, has this many (*) dimensions. It is the maximum number of colors needed to color a plane, and is the smallest positive non-Fibonacci number. For ten points, what number, the number of faces of a tetrahedron, is equal to two squared?
This number is the smallest composite Motzkin number, and a theorem based on this number was proven in 1976 by Wolfgang Haken and Kenneth Appel.
{Four}