Chứng minh A < 1/37

----- Nội dung ảnh -----
A = \(\frac{1}{6^2} + \frac{1}{6^4} + \frac{1}{6^6} + \ldots + \frac{1}{6^{998}} + \frac{1}{6^{1000}} < \frac{1}{37}\)