Find the law and fill in the appropriate number in the brackets. 1, 4, 3, 8, 5, 12, 7, how many.
找规律，在括号内填入适当的数.1，4，3，8，5，12，7，多少．
<gadget id="calculator">12 + 4</gadget>
<output>16</output>

<result>16</result>