$ A =72/65 . 91/84 . 112/ 105 ... 567/ 560 $
A = $\frac{6.12}{5.13}$. $\frac{7.13}{6.14}$. $\frac{8.14}{7.15}$ ...$\frac{21.27}{20.28}$
A= $\frac{6.7.8...21}{5.6.7...20}$. $\frac{12.13.14...27}{13.14.15...28}$= $\frac{21}{5}$ .$\frac{12}{28}$= $\frac{9}{5}$ < 2