What the study found
The authors verify a conjecture that the repetition threshold for the class of rich sequences over d symbols tends to 2 as d grows. A repetition threshold is the smallest number r such that sequences in the class avoid repetitions with exponent greater than r.
Why the authors say this matters
The study suggests that the long-standing pattern observed for smaller alphabets extends to larger ones, with the threshold approaching 2. The authors present this as a confirmation of the conjecture made by Currie, Mol, and Peltomäki.
What the researchers tested
The researchers studied the class C_d of d-ary sequences rich in palindromes, meaning sequences containing many palindrome structures. They used this setting to examine the repetition threshold for different alphabet sizes and to test the conjecture about its limiting behavior.
What worked and what didn't
The conjecture was verified: the repetition threshold for C_d tends to 2 as d increases. The abstract does not describe any failed cases, partial results, or exceptions.
What to keep in mind
The abstract does not give details of the proof or the specific values of the thresholds for individual d beyond the previously known cases for d = 2 and d = 3. It also does not describe limitations beyond the scope of the class of rich palindromic sequences.
Key points
- The paper verifies a conjecture about repetition thresholds for rich sequences over d symbols.
- A repetition threshold is the smallest r such that sequences avoid repetitions with exponent greater than r.
- The authors conclude that the threshold for C_d tends to 2 as d grows.
- The study focuses on d-ary sequences rich in palindromes.
- The abstract does not include proof details or additional exceptions.
Disclosure
- Research title:
- Repetition thresholds for rich sequences tend to 2
- Authors:
- Ľubomíra Dvořáková, Edita Pelantová
- Institutions:
- Czech Technical University in Prague
- Publication date:
- 2026-04-23
- DOI:
- 10.37236/14600
- OpenAlex record:
- View
- Image credit:
- Photo by margarita_kochneva on Pixabay · Pixabay License
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