Contravariantly finite subcategories and irreducible maps
Contravariantly finite subcategories and irreducible maps
Let <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="normal upper Lamda"> <mml:semantics> <mml:mi mathvariant="normal">Λ<!-- Λ --></mml:mi> <mml:annotation encoding="application/x-tex">\Lambda</mml:annotation> </mml:semantics> </mml:math> </inline-formula> be an Artin algebra. This paper presents a condition that is necessary for a subcategory of <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="mod normal upper Lamda"> <mml:semantics> <mml:mrow> <mml:mo lspace="thickmathspace" rspace="thickmathspace">mod</mml:mo> <mml:mi mathvariant="normal">Λ<!-- Λ …