k-ary

Summary

A $k$-ary tree is a rooted tree in which every internal vertex has no more than $k$ children. A 1-ary tree is just a path. A 2-ary tree is also called a binary tree, although that term more properly refers to 2-ary trees in which the children of each node are distinguished as being left or right children (with at most one of each type). A $k$-ary tree is said to be complete if every internal vertex has exactly $k$ children.