There is a frog at two points A and B that are one inch apart on a straight line. The frog at point A jumps along a straight line to the symmetrical point A1 about point B, and the frog at point B jumps along a straight line to the symmetrical point B1 about point A. Then, the frog at point A1 jumps along a straight line to point A2, which is symmetrical about point B1, and the frog at point B1 jumps along a straight line to point B2, which is symmetrical about point A1, and so on. After the two frogs have jumped 7 times, how many inches is the distance from the frog at point A to point B?
在直线上两个相距一寸的点A和B上各有一只青蛙．A点的青蛙沿直线跳往关于B点的对称点A1，而B点的青蛙沿直线跳往关于A点的对称点B1．然后，A1点的青蛙沿直线跳往关于B1点的对称点A2，B1点的青蛙沿直线跳往关于A1点的对称点B2，如此跳下去．两只青蛙各跳了7次以后，原来在A点的青蛙跳到的位置距离B点有多少寸．
<gadget id="calculator">3 ** 7</gadget>
<output>2_187</output>

<gadget id="calculator">2_187 - 1</gadget>
<output>2_186</output>

<gadget id="calculator">2_186 / 2</gadget>
<output>1_093</output>

<result>1_093</result>