Still Another Rank Determination of Set Intersection Matrices with an Application in Communication Complexity
نویسنده
چکیده
The set-intersection function gives the cardinality of the intersection of two sets. In order to obtain a lower bound for the communication complexity of this function, the rank of the corresponding characteristic function-value matrices was calculated in 4] and 5]. In this note, the rank of these matrices is determined by another method of proof, which makes use of a factorization into a product of an upper and a lower triangular matrix.
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