Far Eastern Mathematical Journal

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Projective and injective unars


Sakharov I.A.

2024, issue 1, P. 107-119
DOI: https://doi.org/10.47910/FEMJ202410


Abstract
In this paper we study projective and injective unars, as well as unars that satisfy conditions that are weakenings of the concepts of projectivity and injectivity. Namely, an algebraic description of projective, weakly-, quasi- and pseudo-projective, injective, weakly-, quasi- and pseudo-injective unars is given.

Keywords:
projective object, injective object, unar.

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