Recherche
Voici les éléments 1-10 de 20
Counting endomorphisms of crown-like orders
(Springer, 2002-12)
The authors introduce the notion of crown-like orders and introduce powerful tools for counting the endomorphisms of orders of this type.
Least Periods of Factors of Infinite Words
(EDP Sciences, 2009)
We show that any positive integer is the least period of a factor of the Thue-Morse word. We also characterize the set of least periods of factors of a Sturmian word. In particular, the corresponding set for the Fibonacci ...
Non-Repetitive Tilings
(The Electronic Journal of Combinatorics, 2002-07-03)
In 1906 Axel Thue showed how to construct an infinite non-repetitive (or square-free) word on an alphabet of size 3. Since then this result has been rediscovered many times and extended in many ways. We present a two-dimensional ...
Dejean's conjecture holds for n ≥ 27
(EDP Sciences, 2009)
We show that Dejean’s conjecture holds for n ≥ 27. This brings the final resolution of the conjecture by the approach of Moulin Ollagnier within range of the computationally feasible.
Sliding Down Inclines with Fixed Descent Time: a Converse to Galileo's Law of Chords
(Canadian Mathematical Society, 2008-12)
For each a > 2 there is an Infinite Binary Word with Critical Exponent a
(The Electronic Journal of Combinatorics, 2008-08-31)
The critical exponent of an infinite word w is the supremum of all rational numbers α such that w contains an α-power. We resolve an open question of Krieger and Shallit by showing that for each α>2 there is an infinite ...
Self-Complementary Hypergraphs
(University of Ottawa, 2009)
In this thesis, we survey the current research into self-complementary hypergraphs,
and present several new results.
We characterize the cycle type of the permutations on n elements with order equal
to a power of 2 which ...
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.
Vertex-transitive self-complementary uniform hypergraphs of prime order
(Discrete Mathematics, 2009-09)
For an integer n and a prime p, let n(p)=max{i:pidividesn}. In this paper, we present a construction for vertex-transitive self-complementary k-uniform hypergraphs of order n for each integer n such that pn(p)≡1(mod2ℓ+1) ...
Overlap-Free Words and Generalizations
(University of Winnipeg, 2007)
The study of combinatorics on words dates back at least to the beginning of the
20th century and the work of Axel Thue. Thue was the first to give an example of an infinite word over a three letter alphabet that contains ...