In this paper, we construct a new series of prehomogeneous vector spaces from figures made up triangles, which call triangle arrangements. Our main theorem states that, under suitable assumptions, are able to space obtained arrangement by attaching two arrangements corresponding at vertex. We also give examples Many them seem be new.

Abstract This article describes a personal relationship to common green space in town the United Kingdom during lockdowns prompted by Covid-19 pandemic 2020–21. It considers new meanings that are attaching ‘commons’ as conceptual spaces and material places; it links this consideration terms which values norms being reassessed context of environmental crises.