本論文在討論 Kneser 圖的環色數。 假如 m 大於或等於
2n^{2}(n-1) ，則Kneser 圖KG(m,n)
的環色數會相等於它的著色數這是已經知道的。
尤其是當 m 大於或等於 36 時，假如 n 等於 3，則KG(m,3)
的環色數會與本身的著色數相等。
在本論文中我們藉由假如 m 大於或等於 24，則
chi_{c}(KG(m,3)) = chi(KG(m,3))
這個證明來改善這個結果。

This thesis studies the circular chromatic number of Kneser
graphs. It was known that if m is
greater than 2n^{2}(n-1), then the Kneser graph KG(m,n) has its circular chromatic number
equal its chromatic number . In particular, if
n = 3, then KG(m,3) has its circular chromatic number equal its
chromatic number when m is greater than 36. In this thesis, we improve
this result by proving that if m is
greaer than 24, then chi_c(KG(m,3)) = chi(KG(m,3)).

Contents
1 Introduction 1
2 Some preliminaries 3
3 The main result 6

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