A Balmer middle school teacher successfully obtained the Balmer formula from the spectral data (9/5), (16/12), (25/21), (36/32), ..., thus opening the door to the mysteries of the spectrum, Please follow this rule and write down the number of the 9th data.
一个巴尔末的中学教师成功地从光谱数据(9/5)，(16/12)，(25/21)，(36/32)，…中得到巴尔末公式，从而打开了光谱奥秘的大门，请你按照这种规律，写出第9个数据是多少．
<gadget id="calculator">12 ** 2</gadget>
<output>144</output>

<gadget id="calculator">144 - 4</gadget>
<output>140</output>

<gadget id="calculator">144 / 140</gadget>
<output>36/35 = around 1.028571</output>

<result>36/35 = around 1.028571</result>