शृंखला में कौन सी संख्या अगली आएगी? 1, 2, 3, 5, 8, _____

Each term is the sum of the two before it (Fibonacci): 1 + 2 = 3, 2 + 3 = 5, 3 + 5 = 8, 5 + 8 = 13.