Explicit unique-neighbor expanders

  title={Explicit unique-neighbor expanders},
  author={Noga Alon and Michael R. Capalbo},
  journal={The 43rd Annual IEEE Symposium on Foundations of Computer Science, 2002. Proceedings.},
  • N. Alon, Michael R. Capalbo
  • Published 16 November 2002
  • Mathematics, Computer Science
  • The 43rd Annual IEEE Symposium on Foundations of Computer Science, 2002. Proceedings.
We present a simple, explicit construction of an infinite family F of bounded-degree 'unique-neighbor' expanders /spl Gamma/; i.e., there are strictly positive constants /spl alpha/ and /spl epsi/, such that all /spl Gamma/ = (X, E(/spl Gamma/)) /spl isin/ F satisfy the following property. For each subset S of X with no more than /spl alpha/|X| vertices, there are at least /spl epsi/|S| vertices in X/spl bsol/S that are adjacent in /spl Gamma/ to exactly one vertex in S. The construction of F… 
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