Chapter 12 - Section 12.1 - Sequences and Summation Notation - 12.1 Exercises - Page 851: 35

$A_{n}=$$(2n-1)/n^2$

The denominator in each term is always a square, in fact if we look carefully it's always $n^2$. And the numerators are all odd in fact follow the pattern $2n-1$. Combine these 2 and we get the final answer of $(2n-1)/n^2$.