TITLE: GCN CIRCULAR NUMBER: 15350 SUBJECT: GRB131018A, optical observations DATE: 13/10/18 13:22:50 GMT FROM: Arne A. Henden at AAVSO Arne Henden (AAVSO), as part of a larger collaboration, reports: We observed the field of GRB131018A using the Mt. John University Observatory Optical Craftsman 61cm telescope (part of AAVSOnet), with observations starting at 12:55:24 UT (7.6 minutes after the Swift trigger) under poor seeing conditions and bright moonlight. We do not see any optical afterglow at the XRT position to a limiting magnitude of R=17 (using APASS calibrations). [GCN OPS NOTE(18oct13): The "A' suffix was added to the GRB name.]