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Exercise 1.12.  The following pattern of numbers is called Pascal's triangle.The numbers at the edge of the triangle are all 1, and each number inside the triangle is the sum of the two number

Exercise 1.11.  A function f is defined by the rule that f(n) = n if n<3 and f(n) = f(n - 1) + 2f(n - 2) + 3f(n - 3) if n> 3. Write a procedure that computes f by means of a recursive proces