1.
Chen P, Mei Z, Wang S. Inversion Formulae on Permutations Avoiding 321. Electron. J. Combin. [Internet]. 2015Nov.13 [cited 2026Mar.27];22(4):P4.28. Available from: https://www.combinatorics.org/ojs/index.php/eljc/article/view/v22i4p28