Número de Ramsey relativo a arestas de potências de caminhos
Resumo
Dados grafos G e H e um inteiro positivo q, dizemos que G é q-Ramsey para H se toda q-coloração das arestas de G contém uma cópia monocromática de H. Denotamos essa propriedade por G ⭢ (H)q. O número de Ramsey relativo a arestas r̂(H) de um grafo H é definido como r̂(H) = min{|E(G)|: G ⭢ (H)2}. Respondendo uma pergunta sugerida por Conlon, provamos que r̂(Pnk) = O(n) para todo k fixo, onde Pnk é a k-ésima potência do caminho com n vértices Pn, i.e., o grafo com conjunto de vértices V(Pn) e todas as arestas {u, v} tais que a distância entre u e v em Pn é no máximo k.
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