On Determination of the Irredundant Covers of a Prime Implicant Table

摘要

An algorithm for generating the irredundant covers of a prime implicant table is discussed in this paper. The method depends on a representation of the prime implicant table on a 'prime implicant lattice' defined in terms of a partial ordering which takes its motivation from the equation x + xy = x. The problem is formulated in terms of certain properties on the lattice and a solution primarily based on geometrical interpretation is proposed. The novelty in our formulation lies in the fact that the solution is expressed as a product-of-sums expression which has factors with both uncomplemented and complemented variables. The presence of these factors with complemented variables can be profitably utilized to yield an efficient branching procedure for reducing the redundancy. (Author)