Title: Nonlocal Venttsel' diffusion in fractal-type domains: regularity results and numerical approximation,
Abstract: We study a nonlocal Venttsel' problem in a non-convex bounded domain with a
Koch-type boundary. Regularity results of the strict solution are proved in
weighted Sobolev spaces. The numerical approximation of the problem is carried
out and optimal a priori error estimates are obtained.