# Article

Full entry | PDF   (0.2 MB)
Keywords:
The radio antipodal number of a graph $G$ is the smallest integer $c$ such that there exists an assignment $f\: V(G)\rightarrow \lbrace 1,2,\ldots ,c\rbrace$ satisfying $|f(u)-f(v)|\ge D-d(u,v)$ for every two distinct vertices $u$ and $v$ of $G$, where $D$ is the diameter of $G$. In this note we determine the exact value of the antipodal number of the path, thus answering the conjecture given in [G. Chartrand, D. Erwin and P. Zhang, Math. Bohem. 127 (2002), 57–69]. We also show the connections between this colouring and radio labelings.
[4] G. Chartrand, L. Nebeský, P. Zhang: Radio $k$-colorings of paths. Discuss. Math. Graph Theory 24 (2004), 5–21. DOI 10.7151/dmgt.1209 | MR 2118291
[5] D. Kuo, J.-H. Yan: On $L(2,1)$-labelings of Cartesian products of paths and cycles. Discrete Math. 283 (2004), 137–144. DOI 10.1016/j.disc.2003.11.009 | MR 2061491