# 零是偶数还是奇数

But why did Mayor Bloomberg say even numbers and zero ? Was it necessary to single zero out? It seemed a little odd to us. So we talked to Dr James Grime of the Millennium Maths Project at Cambridge University in the UK. And he says that the a similar issue came up in France in the 1970s.

In 1977, the smog in Paris was so bad that we they had to restrict car use. So they used the same method that they use they’re using in New York now. , alternating days for odd and even license plate licence plates numbers. And the police did not know whether to stop , the zero-numbered licence plates. Actually, and so they just let them pass because they didn’t know whether that it was odd or even.

So it seems not everyone is sure . but do mathematicians agree over of whether zero is odd or even?

The debate is settled among mathematicians.

Mathematicians are agreed that zero is an even number?

Zero is an even number, and it will pass every test and every definition of an even number.

Well, what are the usual tests or definitions for even numbers?

If you take a number and you double it, the result will be an even number. So if you take the number 3 three, and you double it, then you will you’ll get 6 six. And 6 six is an even number. So that would will be the definition of even numbers. And zero will pass that test. So if you double zero, you will you’ll get zero. But it will pass all the other tests for even numbers as well. If you alternate the even and odd numbers, then zero is between two odd numbers. It’s between 1 one and -1. minus one. That’s another example of the a test that it would pass.

• Words worth to be remembered:
• single out : 挑选出 例句： We all did well, but the teacher singled him out for praise. 我们都做得很好，但老师就表扬了他一个人。

## 譯文

“1977年，巴黎弥漫着大量烟雾，空气质量十分糟糕，政府不得不采取措施限制汽车的使用。他们的方法和现在纽约市采用的方法一样，即单双号车辆隔日出行。警察不知道零是单数还是双数，也不知道该不该拦下车牌尾号为零的车辆，只好让这些车开走。”

“看来并不是所有人都确定零是奇数还是偶数，不过，数学家在这个问题上意见统一吗？”

“数学家的看法是一致的。”

“他们认为零是偶数？”

“零是偶数，它通过了所有测试，符合偶数的所有定义。”

“对偶数的测试和定义都有哪些？”

“把一个数乘以2可以得到一个偶数。如果你把3乘以2，结果是6。6就是一个偶数。这就是对偶数的定义。零也符合这条定义。如果你把零乘以2，结果是零。它还通过了其它测试。如果把奇数和偶数间隔排列，零位于两个奇数1和-1之间，它也通过了这项测试。”

##### Chaochen Wang 王　超辰
###### Assistant Professor

All models are wrong, but some are useful.