论文标题
地形般的图和中间的人群数字
Terrain-like Graphs and the Median Genocchi Numbers
论文作者
论文摘要
带有顶点集$ \ {1，\ ldots，n \} $的图形类似于地形，如果对于任何边缘对$ \ {a，c \}，\ {b，d \} $，带有$ a <b <c <d $，边缘$ \ \ {a，d \} $也存在。地形样图在可见性图的背景下经常出现在几何形状中。我们表明，地形样图是由中位基因科奇数计数的。为此，我们证明了类似地形的图与第二种的杜蒙（Dumont）毁灭之间的两者进行了两者。
A graph with vertex set $\{1,\ldots,n\}$ is terrain-like if, for any edge pair $\{a,c\},\{b,d\}$ with $a<b<c<d$, the edge $\{a,d\}$ also exists. Terrain-like graphs frequently appear in geometry in the context of visibility graphs. We show that terrain-like graphs are counted by the median Genocchi numbers. To this end, we prove a bijection between terrain-like graphs and Dumont derangements of the second kind.
