LOCALLY TRIANGULAR GRAPHS AND NORMAL QUOTIENTS OF THE n-CUBE
نویسنده
چکیده
For an integer n > 2, the triangular graph has vertex set the 2-subsets of {1, . . . , n} and edge set the pairs of 2-subsets intersecting at one point. Such graphs are known to be halved graphs of bipartite rectagraphs, which are connected triangle-free graphs in which every 2-path lies in a unique quadrangle. We refine this result and provide a characterisation of connected locally triangular graphs as halved graphs of normal quotients of n-cubes. To do so, we study a parameter that generalises the concept of minimum distance for a binary linear code to arbitrary automorphism groups of the n-cube.
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تاریخ انتشار 2015