证明:令$displaystylealpha = mathop {inf }limits_{n ge 1} left{ {frac{{ln {a_n}}}{n}} ight}$,由下极限的定义知[alpha le mathop {underline {lim } }limits_{n o infty } frac{{ln {a_n}}}{n}]
证明:令$displaystylealpha = mathop {inf }limits_{n ge 1} left{ {frac{{ln {a_n}}}{n}} ight}$,由下极限的定义知[alpha le mathop {underline {lim } }limits_{n o infty } frac{{ln {a_n}}}{n}]