A Counterexample to a Question of Hof, Knill and Simon
A Counterexample to a Question of Hof, Knill and Simon
In this article, we give a negative answer to a question of Hof, Knill and Simon (1995) concerning purely morphic sequences obtained from primitive morphism containing an infinite number of palindromes. Their conjecture states that such palindromic sequences arise from substitutions that are in class $\mathcal{P}$. The conjecture was proven …