Codimension 1 orbits and semi-invariants for the representations of an oriented graph of type ๐_{๐}
Codimension 1 orbits and semi-invariants for the representations of an oriented graph of type ๐_{๐}
We consider the Dynkin diagram <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="script upper A Subscript n"> <mml:semantics> <mml:msub> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mi class="MJX-tex-caligraphic" mathvariant="script">A</mml:mi> </mml:mrow> <mml:mi>n</mml:mi> </mml:msub> <mml:annotation encoding="application/x-tex">\mathcal {A}_n</mml:annotation> </mml:semantics> </mml:math> </inline-formula> with an arbitrary orientation <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="normal upper Omega"> <mml:semantics> <mml:mi mathvariant="normal">ฮฉ<!-- ฮฉ --></mml:mi> <mml:annotation encoding="application/x-tex">\Omega</mml:annotation> </mml:semantics> </mml:math> โฆ