# Prime numbers Search

This tool searches for prime numbers based on an integer n that you enter.

Explanations about prime numbers,:

- Definition of a prime number

- Method to check the primality of a number

- List of prime numbers,

are on this page: Primality test

## Programming

### Python

This program lists the prime number within a given interval [a, b]. More precisely, it returns the number of prime numbers between a and b.

- As an intermediate step, we use the python prime number test.

- We go through the interval [a, b] with a for loop (index i). If i is prime, it is added to the list (mylist) with the append method.

- n% i means the remainder of the Euclidean division of n by i. If n% i = 0 then i divides n.

```
def is_prime (number):
#1 is not prime
if (number == 1):
return False
for i in range (2, number):
if number% i == 0:
return False
return True
def prime_numbers(a, b):
mylist = []
for i in range (a, b+1):
if is_prime (i):
mylist.append(i)
return len(mylist), mylist
```