The Spectrum and Automorphism Group of the Set-Inclusion Graph.

Let n , k and l be integers with 1 ≤ k < l ≤ n − 1. The set-inclusion graph G (n , k , l) is the graph whose vertex set consists of all k - and l -subsets of [ n ] = { 1 , 2 , ... , n } , where two distinct vertices are adjacent if one of them is contained in the other. In this paper, we determine the spectrum and automorphism group of G (n , k , l). [ABSTRACT FROM AUTHOR]