American Mathematical Monthly
Counting permutations with given cycle structure and descent set
Journal of Combinatorial Theory Series A
Descent classes of permutations with a given number of fixed points
Journal of Combinatorial Theory Series A
Permutation tableaux and permutation patterns
Journal of Combinatorial Theory Series A
Alternating permutations and symmetric functions
Journal of Combinatorial Theory Series A
Fix-Mahonian calculus, I: Two transformations
European Journal of Combinatorics
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We extend Stanley's work on alternating permutations with extremal number of fixed points in two directions: first, alternating permutations are replaced by permutations with a prescribed descent set; second, instead of simply counting permutations we study their generating polynomials by number of excedances. Several techniques are used: Desarmenien's desarrangement combinatorics, Gessel's hook-factorization and the analytical properties of two new permutation statistics ''DEZ'' and ''lec.'' Explicit formulas for the maximal case are derived by using symmetric function tools.