(graph theory, computer science, discrete mathematics:)

A connected (undirected!) graph with no cycles. A finite tree on n vertices has exactly n-1 edges.

In computer science, trees are often in fact rooted trees. (In the finite case, this is the same thing as being a directed tree; however infinite trees can be directed without having a root.)

• graph theory
• computer science
• discrete mathematics
• connected
• graph
• cycle
• finite
• edge
• rooted tree
• finite

• vertices
• the same thing as
• directed tree