A binary tree in which special nodes are added wherever a null subtree was present in the original tree so that each node in the original tree (except the root node) has degree three (Knuth 1997, p. 399).

# Extended Binary Tree

## See also

Binary Tree## Explore with Wolfram|Alpha

## References

Knuth, D. E.*The Art of Computer Programming, Vol. 1: Fundamental Algorithms, 3rd ed.*Reading, MA: Addison-Wesley, 1997.

## Referenced on Wolfram|Alpha

Extended Binary Tree## Cite this as:

Weisstein, Eric W. "Extended Binary Tree."
From *MathWorld*--A Wolfram Web Resource. https://mathworld.wolfram.com/ExtendedBinaryTree.html