Definition:Rooted Tree/Root Node

This page is about Root Node in the context of Rooted Tree. For other uses, see Root.

Definition

Let $T$ be a rooted tree.

The root node of $T$ is the node of $T$ which is distinguished from the others by being the ancestor node of every node of $T$.

Also known as

The root node of a rooted tree can be referred to as just the root.

Examples

Arbitrary Example

Consider the rooted tree below:

The root node is node $1$.

Also see

• Results about root nodes can be found here.

Sources

• 1996: H. Jerome Keisler and Joel Robbin: Mathematical Logic and Computability ... (previous) ... (next): $\S 1.7$: Tableaus