The page numbers of a book are continuous natural numbers: 1, 2, 3, 4, ..., when these page numbers are added up, a certain page number is added twice, and the incorrect result 2009 is obtained, then this is added twice What is the page number of this time.
一本书的页码是连续的自然数：1，2，3，4，…，当将这些页码加起来的时候，某个页码加了两次，得到不正确的结果2009，则这个被加了两次的页码是多少．
<gadget id="calculator">62 + 1</gadget>
<output>63</output>

<gadget id="calculator">63 / 2</gadget>
<output>63/2 = around 31.5</output>

<gadget id="calculator">62 * (63/2)</gadget>
<output>1_953</output>

<gadget id="calculator">2_009 - 1_953</gadget>
<output>56</output>

<result>56</result>