Dongjie Elementary School organized a square formation to participate in the gymnastics competition of the whole town. Later, in order to unify the number of participating teams in the whole town, Dongjie Elementary School had to reduce each row by one row and one row vertically. In this way, 17 people were removed in total. How many people were there in the phalanx?
东街小学为参加全镇的体操比赛组织了一个正方形的方阵，后来，全镇为统一各参赛队的人数，东街小学只好横竖各减少一排，这样共去掉了17人．原来方阵有多少人？
<gadget id="calculator">17 + 1</gadget>
<output>18</output>

<gadget id="calculator">18 / 2</gadget>
<output>9</output>

<gadget id="calculator">9 * 9</gadget>
<output>81</output>

<result>81</result>