Given S=\{2,5,8,11,14,17,20 \ldots\}. Given that one can choose n different numbers from S, \left\{A_{1}, A_{2}, \ldots A_{n}\right\}, s.t. \sum_{i=1}^{n} \frac{1}{A_{i}}=1. Find the minimum possible value of \mathrm{n}.
Given S=\{2,5,8,11,14,17,20 \ldots\}. Given that one can choose n different numbers from S, \left\{A_{1}, A_{2}, \ldots A_{n}\right\}, s.t. \sum_{i=1}^{n} \frac{1}{A_{i}}=1. Find the minimum possible value of \mathrm{n}.