The Crossing Number of C(m,3)
C(m,3)的交叉数

It is well known that determination of the exact value of the crossing number for any nontrivial type of graphs is very difficult. This paper shows that for each $k \ge 2$ and $ h \in \{0,1,2\}$ the crossing number is $k+h$ for the circular graph $C(3k+h,3)$, and 1 for $C(m,3)$ with $m{=}5,6,7$.