Hyperfactord of Shi arrangement Sh(A2) and Sh(A3)


  • Alaa A. A. Al-Mujmaey Department of Mathematics, College of Science, Mustansiriyah University, Baghdad, IRAQ.
  • Rabeaa G. A. Al-Aleyawee Department of Mathematics, College of Science, Mustansiriyah University, Baghdad, IRAQ.




Hyperplane arrangement, Briad arrangement, Shi arrangement.


In this paper, we introduce the region and the faces poset of shi arrangement that J. Y. Shi firstly introduced it. This is an affine arrangement, each of whose hyperplane is parallel to some"hyperplane of Coxeter arrangement"(Braid arrangement), the degrees and the exponents of this arrangement were found and we prove the shi arrangement is ahyperfactored arrangement when n=3 and not hyperfactored arrangement when n=4 arrangement.





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How to Cite

A. A. A. Al-Mujmaey and R. G. A. . Al-Aleyawee, “Hyperfactord of Shi arrangement Sh(A2) and Sh(A3)”, Al-Mustansiriyah Journal of Science, vol. 33, no. 3, pp. 43–47, Sep. 2022.