This research is concerned with the analysis of very large systems of linear and integral equations having some particular mathematical structure and with the derivation of efficient algorithms for such equations. This includes 1)analysis of the definition of recursive and parallel recursive structure of matrices and kernels; 2)algorithm design for implementation on modern computer architectures; 3)convergence and complexity analysis of difference schemes for the numerical solution of integral equations with structured kernel; and 4)roundoff error analysis of fast algorithms.