A cut-vertex in a graph G is a vertex whose removal increases the number of connected components of G. An end-block of G is a block with a single cut-vertex. In this paper we establish upper bounds on the numbers of end-blocks and cut-vertices in a 4-regular graph G and claw-free 4-regular graphs. We characterize the extremal graphs achieving these bounds.
@article{bwmeta1.element.doi-10_7151_dmgt_1724, author = {Dingguo Wang and Erfang Shan}, title = {On the Numbers of Cut-Vertices and End-Blocks in 4-Regular Graphs}, journal = {Discussiones Mathematicae Graph Theory}, volume = {34}, year = {2014}, pages = {127-136}, zbl = {1292.05150}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.doi-10_7151_dmgt_1724} }
Dingguo Wang; Erfang Shan. On the Numbers of Cut-Vertices and End-Blocks in 4-Regular Graphs. Discussiones Mathematicae Graph Theory, Tome 34 (2014) pp. 127-136. http://gdmltest.u-ga.fr/item/bwmeta1.element.doi-10_7151_dmgt_1724/
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