Which recursive formula can be used to generate the sequence below, where f(1) = 6 and n ≥ 1? 6, 1, –4, –9, –14, … f (n 1) = f(n) 5 f (n 1) = f(n) – 5 f (n) = f(n 1 ) – 5 f (n 1) = –5f(n)