“…In [5], Avgustinovich and Frid show that any binary word occurs as an arithmetic subsequence of the Thue-Morse sequence (or more generally, a fixed point of any primitive bijective binary constant-length substitution), and go on to investigate properties of the arithmetic complexity of certain words over arbitrary finite alphabets. If we instead consider monochromatic arithmetic subsequences of a given substitutive word and fix the difference of the arithmetic progressions, we note that the length is bounded in the case of the Thue-Morse and more general Thue-Morse-like sequences, as shown, respectively, in [33] and, by the present authors, in [2]; see also [27,28] for results regarding arithmetic progressions in model sets.…”