Retraction Note: Note on “Smaller Explicit Superconcentrators” by N. Alon and M. Capalbo

The author has retracted this article [1], since a critical error was found in the proof of the main result after its publication, thus making it invalid. The article [1] was written as a note to a paper by N. Alon and M. Capalbo [2].

The author is grateful to Professor A. Yavuz Oruҫ (Department of Electrical and Computer Engineering, University of Maryland, College Park, MD) for pointing to the fallacy in the original article.