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A number of important combinatorial counting problems can be reformulated into the problem of counting the number of leaf nodes on a tree. Since the basic leaf-counting problem is #P-complete, there is strong evidence that no polynomial time algorithm exists for this general problem. Thus, we propose a randomized approximation scheme for this problem, and then empirically compare its convergence rate with the classic method of Knuth. We then give an application of our scheme by introducing a new algorithm for estimating the number of bases of a matroid with an independence oracle.
Cloteaux, B.
and Valentin, L.
(2011),
Counting the Leaves of Trees, Congressus Numerantium, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=908869
(Accessed October 8, 2025)