11.已知递增的等差数列 $\left\{a_{n}\right\}$ 满足 $a_{1}=1, a_{3}=a_{2}{ }^{2}-4$ ,则 $a_{n}=$ $\_\_\_\_$ .
参考答案$\underline{2 n-1}$
2012_退役省自主命题 (2012·理)
11.已知递增的等差数列 $\left\{a_{n}\right\}$ 满足 $a_{1}=1, a_{3}=a_{2}{ }^{2}-4$ ,则 $a_{n}=$ $\_\_\_\_$ .