Write down 5 different natural numbers such that the sum of any three of them can be divisible by 3. What is the minimum sum of these 5 natural numbers?
写出5个不相同的自然数，使其中任意三个自然数的和能被3整除，这5个自然数的和至少是多少．
<gadget id="calculator">0 + 3 + 6 + 9 + 12</gadget>
<output>30</output>

<result>30</result>