50 chess pieces form a circle, number 1, 2, 3, 50 on the chess pieces in a clockwise direction, and then remove every other piece in a clockwise direction until there is only one chess piece left. If the number of the remaining pieces is 42, what is the number of the first piece taken away.
50枚棋子围成一个圆圈，依次按顺时针方向在棋子上编上号码1、2、3、50，然后按顺时针方向每隔一枚拿掉一枚，直到剩下一枚棋子为止．如果剩下的棋子的号码是42，那么第一个被取走的棋子是多少号棋子．
<gadget id="calculator">42 - 36</gadget>
<output>6</output>

<gadget id="calculator">1 + 6</gadget>
<output>7</output>

<result>7</result>