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تسجيل مستخدم جديدB-stable ideals in the nilradical of a Borel subalgebra
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تأليف
Eric Sommers
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We count the number of strictly positive $B$-stable ideals in the nilradical of a Borel subalgebra and prove that the minimal roots of any $B$-stable ideal are conjugate by an element of the Weyl group to a subset of the simple roots. We also compute the number of ideals whose minimal roots are conjugate to a fixed subset of simple roots.
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