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On the rank of a cograph

✍ Scribed by Gerard J. Chang; Liang-Hao Huang; Hong-Gwa Yeh


Book ID
104037436
Publisher
Elsevier Science
Year
2008
Tongue
English
Weight
89 KB
Volume
429
Category
Article
ISSN
0024-3795

No coin nor oath required. For personal study only.

✦ Synopsis


The rank of a graph is defined to be the rank of its adjacency matrix. Royle [G.F. Royle, The rank of a cograph, Electron. J. Combin. 10 (2003) #N11] proved a somewhat surprising result that the rank of a cograph is equal to the number of distinct non-zero rows of its adjacency matrix. In this paper we answer a question posed by Royle (2003) by giving an elementary short proof for a more general setting of this rank property of cographs.


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