Addition chains

Addition chains are sequences of numbers that start with the number 1 and generate subsequent numbers through a series of additions. Specifically, an addition chain for a number \( n \) is a sequence of integers \( a_0, a_1, a_2, \ldots, a_k \) such that: 1. \( a_0 = 1 \) 2. \( a_k = n \) 3.