5 papers
Network pearls climb stairs: a new game on graphs and its optimal solution
Ricky Xiao-Feng Chen
Let be a graph, and and be integers. Suppose there are infinite number of stairs, numbering level , level , etc. How do you place every vertex of the graph on…
The Harer-Zagier and Jackson formulas and new results for one-face bipartite maps
Ricky X. F. Chen
The study of bipartite maps (or Grothendieck's dessins d'enfants) is closely connected with geometry, mathematical physics and free probability. Here we study these objects from th…
The minimum number of chains in a noncrossing partition of a poset
Ricky X. F. Chen
The notion of noncrossing partitions of a partially ordered set (poset) is introduced here. When the poset in question is with the complete order of natural…
Towards studying the structure of triple Hurwitz numbers
Ricky Xiao-Feng Chen
Going beyond the studies of single and double Hurwitz numbers, we report some progress towards studying Hurwitz numbers which correspond to ramified coverings of the Riemann sphere…
Exact enumeration of RNA secondary structures by helices and loops
Ricky X. F. Chen, Christian M. Reidys, Michael S. Waterman
Enumerative studies of RNA secondary structures were initiated four decades ago by Waterman and his coworkers. Since then, RNA secondary structures have been explored according to…