Browsing James D. Currie by Title
Now showing items 35-39 of 39
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A Ternary Square-free Sequence Avoiding Factors Equivalent to abcacba
(The Electronic Journal of Combinatorics, 2016-05-27)We solve a problem of Petrova, finalizing the classification of letter patterns avoidable by ternary square-free words; we show that there is a ternary square-free word avoiding letter pattern xyzxzyx. In fact, we characterize ... -
There are Ternary Circular Square-Free Words of Length n for n ≥ 18
(The Electronic Journal of Combinatorics, 2002-10-11)There are circular square-free words of length n on three symbols for n≥18. This proves a conjecture of R. J. Simpson. -
There Exist Binary Circular 5/2+ Power Free Words of Every Length
(The Electronic Journal of Combinatorics, 2004-01-23)We show that there exist binary circular 5/2+ power free words of every length. -
Unary patterns under permutations
(Elsevier, 2018-06-04)Thue characterized completely the avoidability of unary patterns. Adding function variables gives a general setting capturing avoidance of powers, avoidance of patterns with palindromes, avoidance of powers under coding, ... -
Words without Near-Repetitions
(Canadian Mathematical Society, 1992-06-01)We find an infinite word w on four symbols with the following property: Two occurrences of any block in w must be separated by more than the length of the block. That is, in any subword of w of the form xyx, the length of ...