Concepts inA multiple tree algorithm for the efficient association of asteroid observations
Tree (data structure)
In computer science, a tree is a widely used data structure that simulates a hierarchical tree structure with a set of linked nodes. Mathematically, it is an ordered directed tree, more specifically an arborescence: an acyclic connected graph where each node has zero or more children nodes and at most one parent node. Furthermore, the children of each node have a specific order.
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Combinatorial explosion
In mathematics a combinatorial explosion describes the effect of functions that grow very rapidly as a result of combinatorial considerations. Examples of such functions include the factorial function and related functions. Pathological examples of combinatorial explosion include functions such as the Ackermann function.
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