The leafage l(G) of a chordal graph G is the minimum number of leaves of a tree in which G has an intersection representation by subtrees. We obtain upper and lower bounds on l(G) and compute it on special classes. The maximum of l(G) on n-vertex graphs is n - lg n - 1/2 lg lg n + O(1). The proper leafage l*(G) is the minimum number of leaves when no subtree may contain another; we obtain upper and lower bounds on l*(G). Leafage equals proper leafage on claw-free chordal graphs. We use asteroidal sets and structural properties of chordal graphs.
@article{bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1061, author = {In-Jen Lin and Terry A. McKee and Douglas B. West}, title = {The leafage of a chordal graph}, journal = {Discussiones Mathematicae Graph Theory}, volume = {18}, year = {1998}, pages = {23-48}, zbl = {0912.05053}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1061} }
In-Jen Lin; Terry A. McKee; Douglas B. West. The leafage of a chordal graph. Discussiones Mathematicae Graph Theory, Tome 18 (1998) pp. 23-48. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1061/
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