Summary: M. Herschend, Y. Liu, H. Nakaoka introduced $n$-exangulated categories, which are a simultaneous generalization of $n$-exact categories and $(n+2)$-angulated categories. This paper consists of two results on $n$-exangulated categories: (1) we give an equivalent characterization of axiom (EA2); (2) we provide a new way to construct a closed subfunctor of an $n$-exangulated category.
[8] Ogawa, Y.: Auslander's defects over extriangulated categories: An application for the general heart construction. J. Math. Soc. Japan 73 (2021), 1063-1089. DOI 10.2969/jmsj/84578457 | MR 4329022 | Zbl 1485.18010