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B-stable ideals in the nilradical of a Borel subalgebra

Eric Sommers
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Abstract

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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BibTeXRIS

Eric Sommers. 2003-09-19. B-stable ideals in the nilradical of a Borel subalgebra. https://arxiv.org/abs/math/0303182

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