A conjecture on strong magic labelings of 2-regular graphs

Autor: Jeremy Holden, Dan McQuillan, James M. McQuillan
Rok vydání: 2009
Předmět:
Zdroj: Discrete Mathematics. 309:4130-4136
ISSN: 0012-365X
Popis: Let sC"3 denote the disjoint union of s copies of C"3. For each integer t>=2 it is shown that the disjoint union C"5@?(2t)C"3 has a strong vertex-magic total labeling (and therefore it must also have a strong edge-magic total labeling). For each integer t>=3 it is shown that the disjoint union C"4@?(2t-1)C"3 has a strong vertex-magic total labeling. These results clarify a conjecture on the magic labeling of 2-regular graphs, which posited that no such labelings existed. It is also shown that for each integer t>=1 the disjoint union C"7@?(2t)C"3 has a strong vertex-magic total labeling. The construction employs a technique of shifting rows of (newly constructed) Kotzig arrays to label copies of C"3. The results add further weight to a conjecture of MacDougall regarding the existence of vertex-magic total labeling for regular graphs.
Databáze: OpenAIRE