Key points are not available for this paper at this time.
The critical exponent of an infinite word x is the supremum, over all finite nonempty factors f, of the exponent of f. In this note we show that for all integers k 2, there is a binary infinite k-automatic sequence with critical exponent 7/3. The same conclusion holds for Fibonacci-automatic and Tribonacci-automatic sequences.
Allouche et al. (Mon,) studied this question.