A Simple Counting Formula for Lattice Paths
نویسندگان
چکیده
Let α,β ,x,y be positive integers. Fix a line L : Y = αX + β , and a lattice point Q(x,y) on L. It is well known that the number of lattice paths from the origin to Q which touches L only at Q is given by β x + y ( x + y x )
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