Guichard-Combinatorics-Graph-Theory · Problem 3.5.4
Generating Functions
Mathematics — Probability · catalan-numbers-lattice-paths
Problem
Consider a ``staircase'' as shown below. A path from A to B consists of a sequence of edges starting at A, ending at B, and proceeding only up or right; all paths are of length 6. One such path is indicated by arrows. The staircase shown is a ``3×3'' staircase. How many paths are there in an n×n staircase?