The Rank of a Cograph
نویسنده
چکیده
The rank of the adjacency matrix of a graph is bounded above by the number of distinct non-zero rows of that matrix. In general, the rank is lower than this number because there may be some non-trivial linear combination of the rows equal to zero. We show the somewhat surprising result that this never occurs for the class of cographs. Therefore, the rank of a cograph is equal to the number of distinct non-zero rows of its adjacency matrix.
منابع مشابه
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ورودعنوان ژورنال:
- Electr. J. Comb.
دوره 10 شماره
صفحات -
تاریخ انتشار 2003