--- title: Fibonacci sequence id: 597f24c1dda4e70f53c79c81 challengeType: 5 videoUrl: '' localeTitle: 斐波那契序列 --- ## Description

编写一个函数来生成第n Fibonacci数。

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n Fibonacci数由下式给出:///

F n = F n-1 + F n-2

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该系列的前两个术语是0,1。

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因此,该系列是:0,1,1,2,3,5,8,13 ......

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## Instructions
## Tests
```yml tests: - text: fibonacci是一种功能。 testString: 'assert(typeof fibonacci === "function", "fibonacci is a function.");' - text: fibonacci(2)应该返回一个数字。 testString: 'assert(typeof fibonacci(2) == "number", "fibonacci(2) should return a number.");' - text: fibonacci(3)应该返回1.“) testString: 'assert.equal(fibonacci(3),1,"fibonacci(3) should return 1.");' - text: fibonacci(5)应该返回3.“) testString: 'assert.equal(fibonacci(5),3,"fibonacci(5) should return 3.");' - text: fibonacci(10)应该返回34.“) testString: 'assert.equal(fibonacci(10),34,"fibonacci(10) should return 34.");' ```
## Challenge Seed
```js function fibonacci(n) { // Good luck! } ```
## Solution
```js // solution required ```