| 释义 |
Petersen graph Math.|ˈpiːtəsən|
[Named after Julius Petersen (1839–1910), Danish mathematician, who first devised it (L'Intermédiaire des Mathématiciens (1898) V. 227).]
A graph having ten vertices and fifteen lines, which may be drawn as a pentagram disposed symmetrically within a pentagon, each vertex of the latter being joined by a line to the nearest vertex of the former.
1947Proc. Camb. Philos. Soc. XLIII 460 The 5-cage is the ‘Petersen graph’. 1962O. Ore Theory of Graphs xv. 240 The so-called Petersen graph has the form indicated in Figure 15.1.3. It is regular of degree 3 and order 10. It was first introduced by Petersen as an illustration of a graph with ρ = 3 which is not the sum of 3 subgraphs of first degree. 1976Sci. Amer. Apr. 127/1 The other class of uncolorable trivalent maps Tait missed are all nonplanar (impossible to draw on the plane without at least one intersecting edge). The simplest example, known as the Petersen graph, is shown in the upper illustration at the right. |