This graph is interesting as it has chromatic number 4,
but it contains no triangles, which makes it hard to check it.
The Grötzsch graph coincides with the third Mycielski graph.
Grötzsch's Theorem: Any triangle-free planar graph is 3-colorable.
HELP: Who was/is Grötzsch ? If you know anything about this person, please send me a note with info for this page.
The harmonic evolution digraph consists of:
| Loops | = | L1 + 51 L5 | |
| Tree | = | T1 * T22 |