Tag Archives: Paul Erdos

Asymptotic group theory, 3

A Ramanujan graph is a connected finite graph of valency k whose eigenvalues (apart from k and −k) all have modulus at most 2√(k−1). This interval is the spectrum of the infinite k-valent tree T (regarded as an operator on … Continue reading

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From the archive, 5

The first of my two papers with Paul Erdős was published in 1990 in a conference proceedings, and is a bit inaccessible; I have never managed to find a copy on the web. The Hungarians are collecting electronic copies of … Continue reading

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South-eastern

The South-Eastern International Conference on Combinatorics, Graph Theory and Computing has been going for 44 years. I am not sure of its early history. For some time it alternated between Boca Raton (Florida) and Baton Rouge (Louisiana), but now it … Continue reading

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