A complete 4-partite graph is called d-halvable if it can be decomposed into two isomorphic factors of diameter d. In the class of graphs with at most one odd part all d-halvable graphs are known. In the class of biregular graphs with four odd parts (i.e., the graphs and ) all d-halvable graphs are known as well, except for the graphs when d = 2 and n ≠ m. We prove that such graphs are 2-halvable iff n,m ≥ 3. We also determine a new class of non-halvable graphs with three or four different odd parts.
@article{bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1079, author = {Dalibor Fron\v cek}, title = {2-halvable complete 4-partite graphs}, journal = {Discussiones Mathematicae Graph Theory}, volume = {18}, year = {1998}, pages = {233-242}, zbl = {0934.05103}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1079} }
Dalibor Fronček. 2-halvable complete 4-partite graphs. Discussiones Mathematicae Graph Theory, Tome 18 (1998) pp. 233-242. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1079/
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