The park originally planned to plant a solid square with 24 trees on each side, but now it is necessary to set aside a place in the middle to build a small pavilion. If you add 24 more trees and want to plant a hollow square matrix with 5 layers, ask how many trees should be planted in the innermost layer.
公园原计划用树栽种一个实心方阵，每边24棵，现要留出中间的地方修建一个小亭．如果再增加24棵树，想种成5层的空心方阵，问最内层应种多少棵树．
<gadget id="calculator">24 * 24</gadget>
<output>576</output>

<gadget id="calculator">576 + 24</gadget>
<output>600</output>

<gadget id="calculator">600 / 5</gadget>
<output>120</output>

<gadget id="calculator">8 * 2</gadget>
<output>16</output>

<gadget id="calculator">120 - 16</gadget>
<output>104</output>

<result>104</result>