KNOWING That Let p(x) = x -c1xk-1-c2xx-2-... - Ck, let a1, ..., am be roots of the polyno- mial p (not necessarily all of the roots), and let B1. ... . Bm be arbitrary real numbers. an = BI . an + . . . + Bm . am (n = 1, 2, ... ) satisfies the recurrence relation (recursion) an =cian-1 + C2an-2+ . . . + Ckan-k for all n > k. (H) 4.5. Give a closed formula for the nth term of the sequence ao = 0, a1 = 0, a2 = 1, an =an-1 +an-2-an-3 (n>3)