Enumerating Trees

2012/01/09 by Robert A. Kucharczyk, Kucharczyk, Robert A.
Mathematics · #Combinatorics (math.CO) #FOS: Mathematics #Number Theory (math.NT) #math.CO #math.NT

paper · pdf · doi:10.48550/arxiv.1201.1851

15 pages, 1 figure

arxiv created 2012/01/09 · arxiv updated 2012/01/10

Abstract

In this note we discuss trees similar to the Calkin-Wilf tree, a binary tree that enumerates all positive rational numbers in a simple way. The original construction of Calkin and Wilf is reformulated in a more algebraic language, and an elementary application of methods from analytic number theory gives restrictions on possible analogues.

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