Two classes of extreme graphs related to the maximum degree of an interchange graph
نویسنده
چکیده
Let U(R, S) denote the class of all m x n matrices of O's and l's having row sum vector R and column sum vector S. The interchange graph G (R, S) is the graph where the vertices are the matrices in U (R, S) and two vertices are adjacent provided they differ by an interchange. Two tight upper-bounds of the maximum degree l:l.(G(R, S)) are given. Furthermore, those extreme graphs whose maximum degrees reach the upper-bounds are determined.
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عنوان ژورنال:
- Australasian J. Combinatorics
دوره 19 شماره
صفحات -
تاریخ انتشار 1999