Total interval numbers of complete r-partite graphs
نویسندگان
چکیده
A multiple-interval representation of a graph G is a mapping f which assigns to each vertex of G a union of intervals on the real line so that two distinct vertices u and v are adjacent if and only if f(u) ∩ f(v) = ∅. We study the total interval number of G, de0ned as I(G) = min {∑ v∈V #f(v): f is a multiple-interval representation of G } ; where #f(v) is the minimum number of intervals whose union is f(v). We give bounds on the total interval numbers of complete r-partite graphs. Exact values are also determined for several cases. ? 2002 Elsevier Science B.V. All rights reserved.
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عنوان ژورنال:
- Discrete Applied Mathematics
دوره 122 شماره
صفحات -
تاریخ انتشار 2002