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Grunbaum, Branko
Every 4-connected toroidal graph has a Hamilton cycle ★★
Author(s): Grunbaum; Nash-Williams
Conjecture Every 4-connected toroidal graph has a Hamilton cycle.
Keywords:
4-regular 4-chromatic graphs of high girth ★★
Author(s): Grunbaum
Problem Do there exist 4-regular 4-chromatic graphs of arbitrarily high girth?
Grunbaum's Conjecture ★★★
Author(s): Grunbaum
Conjecture If
is a simple loopless triangulation of an orientable surface, then the dual of
is 3-edge-colorable.
![$ G $](/files/tex/b8e7ad0330f925492bf468b5c379baec88cf1b3d.png)
![$ G $](/files/tex/b8e7ad0330f925492bf468b5c379baec88cf1b3d.png)
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