There are 18 seats in a row in the cinema, and my mother wants Xiaojun to sit next to her. How many different ways of sitting are there in the same row?
电影院里一排有18个座位，妈妈想让小军坐在自己的旁边．在同一排有多少种不同的坐法？
<gadget id="calculator">18 - 1</gadget>
<output>17</output>

<gadget id="calculator">17 * 2</gadget>
<output>34</output>

<result>34</result>