Descendant in a rooted tree
= Descendant in a rooted tree
= Descendants in a rooted tree
{synonym}
A <vertex> reachable from a specified <vertex> by following child edges in a <rooted tree>. Allowing the length-zero <graph path> includes the starting vertex; a proper descendant excludes it. The <subtree> at a vertex consists of that vertex and its descendants. State the properness convention when using strict discovery-time inequalities.