... interpretation.This interpretation is in line with the rest of this art icle, counting permutations having aninitial descending segment and λ-coloured fixed points to the right of the initial segment. In addition, ... differentiating powers of λ:ddλfλ(n) = n · fλ(n − 1) . (6)the electronic journal of combinatorics 16 (2009), #R32 7 and ψF(σ), inserting elements in increasing order and removing them in decreasing ... Journal of C o mbinatorics, 15:#R71, 2008.[3] Robert J. Clarke, Guo-Niu Han, and Jiang Zeng. A combinatorial interpretation of the Seidel generation of q-derangement numbers. Annals of Combinatorics,...