© 2015 Wiley Periodicals, Inc. We characterize the quartic (i.e., 4-regular) multigraphs with the property that every edge lies in a triangle. The main result is that such graphs are either squares of cycles, line multigraphs of cubic multigraphs, or are obtained from these by a number of simple subgraph-replacement operations. A corollary of this is that a simple quartic graph with every edge in a triangle is either the square of a cycle, the line graph of a cubic graph or a graph obtained from the line multigraph of a cubic multigraph by replacing triangles with copies of K1, 1, 3.
|Number of pages||11|
|Journal||Journal of Graph Theory|
|Publication status||Published - 1 Jun 2016|