Abstract
Let Γ be a strongly regular graph with adjacency matrix A. Let I be the identity matrix, and J the all-1 matrix. Let p be a prime. Our aim is to study the p-rank (that is, the rank over \(\mathbb{F}_p\), the finite field with p elements) of the matrices M = aA + bJ + cI for integral a, b, c. This note is based on van Eijl [8].
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Brouwer, A., Van Eijl, C. On the p-Rank of the Adjacency Matrices of Strongly Regular Graphs. Journal of Algebraic Combinatorics 1, 329–346 (1992). https://doi.org/10.1023/A:1022438616684
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DOI: https://doi.org/10.1023/A:1022438616684