The following column of numbers is arranged according to certain rules, A= how many 1, 4, 13, 40, 121, A, 1093, ...
下面的一列数是按一定的规律排列的，A=多少1、4、13、40、121、A、1093、…
<gadget id="calculator">1 * 3</gadget>
<output>3</output>

<gadget id="calculator">3 + 1</gadget>
<output>4</output>

<gadget id="calculator">4 * 3</gadget>
<output>12</output>

<gadget id="calculator">12 + 1</gadget>
<output>13</output>

<gadget id="calculator">13 * 3</gadget>
<output>39</output>

<gadget id="calculator">39 + 1</gadget>
<output>40</output>

<gadget id="calculator">40 * 3</gadget>
<output>120</output>

<gadget id="calculator">120 + 1</gadget>
<output>121</output>

<gadget id="calculator">121 * 3</gadget>
<output>363</output>

<gadget id="calculator">363 + 1</gadget>
<output>364</output>

<result>364</result>