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A geometrical construction for the polynomial invariants of some reflection groups

Alessandra Sarti
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Abstract

In these notes we investigate the rings of real polynomials in four variables, which are invariant under the action of the reflectiongroups [3,4,3] and [3,3,5]. It is well known that they are rationally generated in degree 2,6,8,12 and 2,12,20,30. We give a different proof of this fact by giving explicit equations for the generating polynomials.

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Alessandra Sarti. 2004-01-20. A geometrical construction for the polynomial invariants of some reflection groups. https://arxiv.org/abs/math/0401254

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