The Fibonacci numbers are the numbers in the following integer sequence.

0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, ……..

In mathematical terms, the sequence Fn of Fibonacci numbers is defined by the recurrence relation

F

_{n}= F_{n-1}+ F_{n-2}with seed values F_{0}= 0 and F_{1}= 1.

**Find the series of fibonacci numbers using lambda function.**

**Code #1 : By using lambda and reduce method**

`from` `functools ` `import` `reduce` ` ` `fib ` `=` `lambda` `n: ` `reduce` `(` `lambda` `x, _: x` `+` `[x[` `-` `1` `]` `+` `x[` `-` `2` `]],` ` ` `range` `(n` `-` `2` `), [` `0` `, ` `1` `])` ` ` `print` `(fib(` `5` `))` |

**Output:**

[0, 1, 1, 2, 3]

**Explanation :**

The list taking first two parameters is 0 and 1, and add like **x[-1]** i.e 0 and **x[-2]** i.e 1 and append to variable x. There is a type conversion to list and due to ** reduce()** method, the same function calls and due to

*range*function this time parameter changes, then add this to previous result and again store it to list.

**Code #2 : By using lambda and map function**

`def` `fibonacci(count):` ` ` `fib_list ` `=` `[` `0` `, ` `1` `]` ` ` ` ` `any` `(` `map` `(` `lambda` `_: fib_list.append(` `sum` `(fib_list[` `-` `2` `:])),` ` ` `range` `(` `2` `, count)))` ` ` ` ` `return` `fib_list[:count]` ` ` `print` `(fibonacci(` `10` `))` |

**Output:**

[0, 1, 1, 2, 3, 5, 8, 13, 21, 34]

**Explanation :**

We are taking the list **fib_list** which already has 0 and 1. Then in the next iteration, this will be used as input and result of their sum will append to the list.

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