6 papers
The average Euler-genus of the vertex-amalgamation of signed graphs
Yichao Chen
In this paper, we first generalize a theorem for counting the number of faces of an oriented embedding of a graph that passing through a given cut-edge set [S. Stahl, Trans. Amer.…
Permutation-bipartition pairs
Yichao Chen
Permutation-partition pairs were introduced by Stahl in 1980. These pairs are generalizations of graphs and graphs on surfaces. They were used to solve some problems for orientable…
Partial-duals for planar ribbon graphs
Qiyao Chen, Yichao Chen
In 2009, Chmutov introduced the partial-duality for a ribbon graph . Recently, Gross, Mansour and Tucker enumerated all possible partial-duals of by genus and introduced the…
The average genus for bouquets of circles and dipoles
Jinlian Zhang, Xuhui Peng, Yichao Chen
The bouquet of circles and dipole graph are two important classes of graphs in topological graph theory. For , we give an explicit formula for the average genu…
Limits for embedding distributions
Jinlian Zhang, Xuhui Peng, Yichao Chen
In this paper, we find and prove that, under some conditions, the embedding distributions of -linear graph families with spiders are asymptotic normal distributions. It can been…
Total embedding distributions of Ringel ladders
Yichao Chen, Lu Ou, Qian Zou
The total embedding distributions of a graph is consisted of the orientable embeddings and non- orientable embeddings and have been know for few classes of graphs. The genus distri…