A step starting at a point P in the XY -plane consists of moving by one unit from P in one of three directions: directly to the right or in the direction of one of the two rays that make the angle of ±120 with positive X-axis. (An opposite move, i.e. to the left/southeast/northeast, is not allowed.) A path consists of a number of such steps, each new step starting where the previous step ended. Points and steps in a path may repeat. Find the number of paths starting at (1,0) and ending at (2,0) that consist of exactly 6 steps
This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try
refreshing the page, (b) enabling javascript if it is disabled on your browser and,
finally, (c)
loading the
non-javascript version of this page
. We're sorry about the hassle.
No explanations have been posted yet. Check back later!