Gyárfás–Lehel Tree Packing Conjecture

From papers

Let T1,,TnT_1,\dotsc,T_n be trees, and let v(Ti)v(T_i) denote the number of vertices of TiT_i. A collection of graphs packs into a graph GG if there are edge-disjoint subgraphs of GG isomorphic to the graphs in the collection. Tree Packing Conjecture. Any collection T1,,TnT_1,\dotsc,T_n of trees with

v(Ti)=iv(T_i)=i

for each ii packs into the complete graph KnK_n. This conjecture concerns packing trees of all sizes into a graph whose order matches the largest tree; its relationship with Ringel's related tree-packing conjecture makes it a central problem in graph decomposition.

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Equivalent formulations 1

Other statements of this same problem, merged from separate entries. Each is equivalent to the statement above — proving any one settles them all.

  1. Gyárfás–Lehel tree packing conjecture

    Let nNn\in\mathbb N and let T1,,TnT_1,\ldots,T_n be trees with Ti=i|T_i|=i. A decomposition of a graph into these trees is a collection of pairwise edge-disjoint copies covering every edge. Gyárfás–Lehel's conjecture. The complete graph KnK_n has a decomposition into copies of T1,,TnT_1,\ldots,T_n. This conjecture motivates optimal packing and decomposition results for families of trees; the paper proves it for families satisfying suitable bounded-degree conditions, but the unrestricted statement remains open.

    source: Felix Joos, Jaehoon Kim, Daniela Kühn and Deryk Osthus, “Optimal packings of bounded degree trees”, arXiv:1606.03953 (2019).

Sources & referencesView supporting material

Primary source

Asaf Ferber and Wojciech Samotij, “Packing trees of unbounded degrees in random graphs”, arXiv:1607.07342 (2016).

Additional references

2 papers in this index state this conjecture (2015–2016). The statement above is taken from the most recent of them; the others are arXiv:1512.08701.

Solutions 0

No solutions have been posted yet.