If the sum of 3 natural numbers (which can be repeated) is 8, what is the maximum product of these 3 natural numbers?
有3个自然数(可以重复)之和为8，则这3个自然数之积最大等于多少．
<gadget id="calculator">3 * 3 * 2</gadget>
<output>18</output>

<result>18</result>