On an anti-Ramsey property of Ramanujan graphs
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چکیده
منابع مشابه
On an Anti-Ramsey Property of Ramanujan Graphs
If G and H are graphs, we write G → H (respectively, G → TH) if for any proper edge-colouring γ of G there is a subgraph H ′ ⊂ G of G isomorphic to H (respectively, isomorphic to a subdivision of H) such that γ is injective on E(H ′). Let us write C for the cycle of length l. Spencer (cf. Erdős [10]) asked whether for any g ≥ 3 there is a graph G = Gg such that (i) G has girth g(G) at least g, ...
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In an edge-coloured host graph G, a subgraph H is properly coloured if no two incident edges of H receive the same colour, and rainbow if no two edges of H receive the same colour. Given a positive integer k, a host graph G, an edge-colouring c of G (c is not necessarily proper), then c is a k-colouring if c uses k colours overall, c is a local k-colouring if at most k colours are used at each ...
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ژورنال
عنوان ژورنال: Random Structures & Algorithms
سال: 1995
ISSN: 1042-9832
DOI: 10.1002/rsa.3240060405