On uniqueness of packing of three copies of 2-factors

The packing of three copies of a graph G is the union of three edge-disjoint copies (with the same vertex set) of G. In this paper, we completely solve the problem of the uniqueness of packing of three copies of 2-regular graphs. In particular, we show that C3,C4,C5,C6 and 2C3 have no packing of three copies, C7,C8,C3∪C4,C4∪C4,C3∪C5 and 3C3 have unique packing, and any other collection of cycles has at least two distinct packings.

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Opracowanie rekordu ze środków MNiSW, umowa nr POPUL/SP/0154/2024/02 w ramach programu "Społeczna odpowiedzialność nauki II" - moduł: Popularyzacja nauki (2025)