30 eggs, one of which has a double yolk, the inspector numbered the eggs and took away all the eggs with odd numbers, but none of them were double yolk eggs. The inspector sorts the remaining eggs, and then takes away the odd eggs, but there are still no double-yolk eggs, and so on, the last one is a double-yolk egg. May I ask: What is the serial number of the first double yolk egg?
30个鸡蛋，其中有一个双蛋黄，检测员给鸡蛋排序号，把单数鸡蛋全部拿走，但是没有一个是双黄蛋．检测员再把剩下的鸡蛋排序，再把单数鸡蛋拿走，可是还是没有双黄蛋，以此类推，最后一个是双黄蛋．请问：双黄蛋第一次的序号是多少？
<gadget id="calculator">2 ** 4</gadget>
<output>16</output>

<result>16</result>