Ultracenter

Ultracenter --- ультрацентр.

The subgraph of the center [math]\displaystyle{ C(G) }[/math] of [math]\displaystyle{ G }[/math] induced by the vertices [math]\displaystyle{ v }[/math] with the central distance [math]\displaystyle{ c(v) = m }[/math] is called the ultracenter of [math]\displaystyle{ g }[/math], which we denote by [math]\displaystyle{ UC(G) }[/math]. The number [math]\displaystyle{ m }[/math] is referred to as the ultraradius of [math]\displaystyle{ G }[/math] which we denote by [math]\displaystyle{ urad(G) }[/math]. In a certain sense, the vertices of [math]\displaystyle{ UC(G) }[/math] are the most central vertices of [math]\displaystyle{ G }[/math].

See also

• Central fringe.