There are More Than 2**(n/17) n-Letter Ternary Square-Free Words

1998/09/23 by Doron Zeilberger
Mathematics · #math.CO

paper · pdf

published as J. Integer Sequences 98.1.9 (1998) · 2 pages (plain TeX)

arxiv created 1998/09/23 · arxiv updated 2009/11/30

Abstract

We prove that the `connective constant' for ternary square-free words is at least 2^1/17 = 1.0416 ... , improving on Brinkhuis and Brandenburg's lower bounds of 2^1/24=1.0293 ... and 2^1/22=1.032 ... respectively. This is the first improvement since 1983.

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