Hungyung Chang

collaborators

4 papers

math.CO2008

Tutte polynomial and G-parking functions

HungYung Chang, Jun Ma, Yeong-Nan Yeh

Let $G$ be a connected graph with vertex set ${0, 1, 2, ..., n}$ . We allow $G$ to have multiple edges and loops. In this paper, we give a characterization of external activity by som…

math.CO2008

(G,m)-multiparking functions

Hungyung Chang, Po-Yi Huang, Jun Ma +1

The conceptions of $G$ -parking functions and $G$ -multiparking functions were introduced in [15] and [12] respectively. In this paper, let $G$ be a connected graph with vertex set $…

math.CO2008

Enumerations for Permutations by Circular Peak Sets

Pierre Bouchard, Hungyung Chang, Jun Ma +1

The circular peak set of a permutation $σ$ is the set ${σ (i) ∣ σ (i - 1) < σ (i) > σ (i + 1)}$ . In this paper, we focus on the enumeration problems for permutations by circular peak sets.…

math.CO2008

Enumerations of Permutations by Circular Descent Sets

Hungyung Chang, Jun Ma, Yeong-Nan Yeh

The circular descent of a permutation $σ$ is a set ${σ (i) ∣ σ (i) > σ (i + 1)}$ . In this paper, we focus on the enumerations of permutations by the circular descent set. Let $cdes_n(…