Title
Lyndon Words, the Three Squares Lemma, and Primitive Squares
Abstract
We revisit the so-called "Three Squares Lemma" by Crochemore and Rytter [Algorithmica 1995] and, using arguments based on Lyndon words, derive a more general variant which considers three overlapping squares which do not necessarily share a common prefix. We also give an improved upper bound of $n\log_2 n$ on the maximum number of (occurrences of) primitively rooted squares in a string of length $n$, also using arguments based on Lyndon words. To the best of our knowledge, the only known upper bound was $n \log_\phi n \approx 1.441n\log_2 n$, where $\phi$ is the golden ratio, mentioned by Fraenkel and Simpson [TCS 1999] based on a theorem by Crochemore and Rytter [Algorithmica 1995] obtained via the Three Squares Lemma.
Year
DOI
Venue
2020
10.1007/978-3-030-59212-7_19
SPIRE
DocType
Citations 
PageRank 
Conference
0
0.34
References 
Authors
0
3
Name
Order
Citations
PageRank
Hideo Bannai162079.87
Takuya Mieno201.01
Yuto Nakashima35719.52