ternary tree
tree data structure in which each node has at most three child nodes, usually distinguished as "left", “mid” and "right"
ternary search tree
3-way tree data structure where every node's left subtree has keys less than the node's key, every middle subtree has keys equal to the node's key, and every right subtree has keys greater than the node's key
tree of primitive Pythagorean triples
data tree in which each node branches to three subsequent nodes with the infinite set of all nodes giving all (and only) primitive Pythagorean triples without duplication