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Inversion polynomials for 321-avoiding permutations: addendum

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 نشر من قبل Bruce E. Sagan
 تاريخ النشر 2013
  مجال البحث
والبحث باللغة English
 تأليف Szu-En Cheng




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This addendum contains results about the inversion number and major index polynomials for permutations avoiding 321 which did not fit well into the original paper. In particular, we consider symmetry, unimodality, behavior modulo 2, and signed enumeration.



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