Connected pseudoachromatic index of complete graphs

نویسندگان

  • Lowell Abrams
  • Yosef Berman
چکیده

A connected pseudocomplete n-coloring of a graph G is a (non-proper) n-coloring of the vertices of G such that each color class induces a connected subgraph and for each pair of color classes there is an edge with one end of each color; this can be viewed as a kind of “inverse image” of a clique minor. The connected pseudoachromatic index of a graph G is the largest n for which the line graph of G has a connected pseudocomplete ncoloring. For all j, k we show that the connected pseudoachromatic index of the complete graph on 5k+j+1 vertices is at least 9k+j. We also provide several results on connections between connected pseudoachromatic index of complete graphs and the Erdős-Faber-Lovasz conjecture.

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عنوان ژورنال:
  • Australasian J. Combinatorics

دوره 60  شماره 

صفحات  -

تاریخ انتشار 2014