Average distance, surface area, and other structural properties of exchanged hypercubes

Exchanged hypercubes (Loh et al. in IEEE Trans Parallel Distrib Syst 16:866-874, 2005) are spanning subgraphs of hypercubes with about one half of their edges but still with many desirable properties of hypercubes. In this paper, it is shown that distance properties of exchanged hypercubes are also comparable to the corresponding properties of hypercubes. The average distance and the surface area of exchanged hypercubes are computed and it is shown that exchanged hypercubes have asymptotically the same average distance as hypercubes. Several additional metric and other properties are also deduced and it is proved that exchanged hypercubes are prime with respect to the Cartesian product of graphs.