Problem 5. (Pascal's Triangle) Pascal's triangle Pn is a triangular array with n1 rows, each listing the coefficients of the binomial expansion (x +y)', where 0 i S n. For example, Ps is the triangular array: 1 3 3 1 The term P (i, j) is calculated as P (1-1, j-1) +Pn(i-1, j), where iS n and l j