If rooms in an office building are allowed to be any rectangular solid, how many colors does it take to paint any configuration of rooms so that no two rooms sharing a wall or ceiling/floor get the same color? In this work, we provide a new construction which shows this number can be arbitrarily large.
@article{bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1535, author = {Colton Magnant and Daniel M. Martin}, title = {Coloring rectangular blocks in 3-space}, journal = {Discussiones Mathematicae Graph Theory}, volume = {31}, year = {2011}, pages = {161-170}, zbl = {1284.05105}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1535} }
Colton Magnant; Daniel M. Martin. Coloring rectangular blocks in 3-space. Discussiones Mathematicae Graph Theory, Tome 31 (2011) pp. 161-170. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1535/
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