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arXiv · 1605.00240

Symmetric Unique Neighbor Expanders and Good LDPC Codes

Oren Becker
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Abstract

An infinite family of bounded-degree 'unique-neighbor' expanders was constructed explicitly by Alon and Capalbo (2002). We present an infinite family F of bounded-degree unique-neighbor expanders with the additional property that every graph in the family F is a Cayley graph. This answers a question raised by Tali Kaufman. Using the same methods, we show that the symmetric LDPC codes constructed by Kaufman and Lubotzky (2012) are in fact symmetric under a simply transitive group action on coordinates.

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Oren Becker. 2016-05-01. Symmetric Unique Neighbor Expanders and Good LDPC Codes. https://doi.org/10.1016/j.dam.2016.04.022

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