Counting Lattice Paths
A lattice has labels A and B at opposite corners. This Demonstration determines the total number of possible paths from A to B, with moves either up or to the right. You can generate a random path from A to B or change the number of columns or rows in the grid. Check "show solution" to display an analog of a Pascal's triangle that gives the total number of possible paths from point A to all other points.
This was a project for Advanced Topics in Mathematics II, 2016–2017, Torrey Pines High School, San Diego, CA.
 M. Coffey and A. Kalish, eds., "Calendar and Solutions—December 2012," Mathematics Teacher, 106(4), 2012. www.nctm.org/Publications/mathematics-teacher/2012/Vol106/Issue4/Calendar-and-Solutions---December-2012.
"Counting Lattice Paths"
Wolfram Demonstrations Project
Published: February 10 2017