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20112026
most citedThe peak and descent statistics over ballot permutations

2 citations · 5 across the 6 of their papers we have counts for

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6 papers

math.CO2026

Classical and vincular patterns of length three in generalized alternating permutations

Zhenhua Luo, Junting Wang, Ziyi Yang +2

Let k be an integer at least 2, and let D_{N,k} be the set of permutations of {1,...,N} whose descent set is exactly {k, 2k, ..., k*floor((N-1)/k)}. We enumerate the elements of D_…

math.CO2021★ 2 cited

A decomposition of ballot permutations, pattern avoidance and Gessel walks

Zhicong Lin, David G. L. Wang, Tongyuan Zhao

A permutation whose any prefix has no more descents than ascents is called a ballot permutation. In this paper, we present a decomposition of ballot permutations that enables us to…

math.CO2021

Refined Eulerian numbers and ballot permutations

Tongyuan Zhao, Yue Sun, Feng Zhao

A ballot permutation is a permutation π such that in any prefix of π the descent number is not more than the ascent number. In this article, we obtained a formula in close form for…

math.CO2020★ 2 cited

The peak and descent statistics over ballot permutations

David G. L. Wang, T. Zhao

A ballot permutation is a permutation such that in any prefix of the descent number is not more than the ascent number. By using a reversal concatenation map, we give a for…

math.CO2015★ 1 cited

Convolution Preserves Partial Synchronicity of Log-concave Sequences

H. Hu, David G. L. Wang, F. Zhao +1

In a recent proof of the log-concavity of genus polynomials of some families of graphs, Gross et al. defined the weakly synchronicity relation between log-concave sequences, and co…

math.CO2011

The Real-Rootedness and Log-concavities of Coordinator Polynomials of Weyl Group Lattices

David G. L. Wang, Tongyuan Zhao

It is well-known that the coordinator polynomials of the classical root lattice of type and those of type are real-rooted. They can be obtained, either by the Aissen-Sc…