A Survey of the Gracefulness of Digraphs
نویسندگان
چکیده
Graph labeling traces its origin to the famous conjecture that all trees are graceful presented by A.Rosa in 1966. In recent years, many research papers on graceful graph have been published. In this survey we have collected studies on the gracefulness of the directed circuit ~ Cm and the union graph of mutually non-intersecting ~ Cm, the digraph n · ~ Cm, the digraph n − ~ Cm, the union of the digraph n · ~ C3, and give some results. AMS Subject Classification: 05C65
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