Abstract Let X (ℤ) X (Z) be a reflexive rearrangement-invariant Banach sequence space and let a be a periodic distribution generating the bounded Laurent operator L (a) L (a) on X (ℤ) X (Z). We prove that if the discrete Wiener–Hopf operator T (a) T (a) is Fredholm on the subspace X (ℤ +) = f = { f k k ∈ ℤ ∈ X (ℤ): f k = 0 for k 0 } X (Z+) =\{f=\{f₊\₊ X (Z): f₊=0% for k T (a) T (a) is left-invertible if κ ≤ 0 0, right-invertible if κ ≥ 0
Karlovych et al. (Thu,) studied this question.