A note on the interval number of a graph
نویسندگان
چکیده
Three results on the interval number of a graph on n vertices are presented. (1) The interval number of almost every graph is between n/4lg n and n/4 (this also holds for almost every bipartite graph). (2) There exist Km,+ -free bipartite graphs with interval number at least c(m)n’-*I( , m+lj/lg n which can be improved to &$4+0(&) for m = 2 and (n/2):/lg n for m = 3. (3) There exists a regular graph of girth at least g with interval number at least &I 1)/2)1'(9-2).
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 55 شماره
صفحات -
تاریخ انتشار 1985