A Combinatorial Formula for Macdonald Cumulants
Séminaire lotharingien de combinatoire, 80B (2018)
Macdonald cumulants are symmetric functions that generalize Macdonald polynomials. We prove a combinatorial formula for them which extends the celebrated formula of Haglund for Macdonald polynomials. We also provide several applications of our formula -- it gives a new, constructive proof of a strong factorization property of Macdonald polynomials and it proves that Macdonald cumulants are q,t-positive in the monomial and in the fundamental quasisymmetric bases. Furthermore, we use our formula to prove the recent higher-order Macdonald positivity conjecture for the coefficients of the Schur polynomials indexed by hooks. Our combinatorial formula links Macdonald cumulants to G-parking functions of Postnikov and Shapiro.
@article{SLC_2018_80B_a40,
author = {Maciej Do{\l}\k{e}ga},
title = {A {Combinatorial} {Formula} for {Macdonald} {Cumulants}},
journal = {S\'eminaire lotharingien de combinatoire},
year = {2018},
volume = {80B},
url = {http://geodesic.mathdoc.fr/item/SLC_2018_80B_a40/}
}
Maciej Dołęga. A Combinatorial Formula for Macdonald Cumulants. Séminaire lotharingien de combinatoire, 80B (2018). http://geodesic.mathdoc.fr/item/SLC_2018_80B_a40/