摘要:通過構造三個循環圖,得到了三個經典Ramsey數R(3,q)的新下界:R(3,34)≥223,R(3,36)≥237, R(3,38)≥254。
關鍵詞:Ramsey數;下界;循環圖
中圖分類號:TP301.6文獻標志碼:A
文章編號:1001-3695(2008)05-1309-03
經典Ramsey數的計算是組合數學中非常困難的問題[1,2]。本文在文獻[3~13]的基礎上,通過構造三個循環圖得到了三個經典Ramsey數的新下界。這些結果是本文首次報道的。
定理1 R(3,34)≥223,R(3,36)≥237, R(3,38)≥254。
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