(17) Consider the sequence {a, } whose terms are defined as follows. 01 = 1, a2 = 3, and an = (an-1 + an-2) for n 2 3. (6) Show that this sequence is Cauchy using the definition of a sequence being Cauchy. Hints: Recall that, "informally", a sequence is Cauchy if we can go "far out enough" into the sequence and get that the difference between any two terms that come after is arbitrarily small. You could try to identify what a, - a, ] is first. Then try to use the triangle inequality to show the desired result for the difference of an arbitrary pair of terms