# Fredholm and invertibility theory for a special class of Toeplitz + Hankel operators

@inproceedings{Basor2011FredholmAI,
title={Fredholm and invertibility theory for a special class of Toeplitz + Hankel operators},
author={Estelle L. Basor and Torsten Ehrhardt},
year={2011}
}
• Published 4 October 2011
• Mathematics
We develop a complete Fredholm and invertibility theory for Toeplitz+Hankel operators T (a) + H(b) on the Hardy space Hp(T), 1 < p < ∞, with piecewise continuous functions a, b defined on the unit circle which are subject to the condition a(t)a(t−1) = b(t)b(t−1), |t| = 1. In particular, in the case of Fredholmness, formulas for the defect numbers are established. The results are applied to several important examples.

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