There are several consecutive odd numbers starting from 1 written on the blackboard: 1, 3, 5, 7, 9, 11, 13... After erasing one of the odd numbers, the sum of all remaining odd numbers is 1998, then the erased What is the odd number.
黑板上写有从1开始的若干个连续的奇数：1，3，5，7，9，11，13…擦去其中的一个奇数以后，剩下的所有奇数之和为1998，那么擦去的奇数是多少．
<gadget id="calculator">45 ** 2</gadget>
<output>2_025</output>

<gadget id="calculator">2_025 - 1_998</gadget>
<output>27</output>

<result>27</result>