Prime numbers



A prime number (or a prime) is a natural number greater than 1 that cannot be formed by multiplying two or more smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number.

To test for whether a number n is prime, test whether the number is divisible by all integers from 2 to the square root of n.

This method trial division is very slow and can improved by other methods such as the AKS primality test.

Readings

 * 1)  Prime number
 * 2)  Generating primes

Multimedia

 * 1) YouTube: Prime Numbers and Composite Numbers
 * 2) YouTube: Prime Numbers - Sieve of Eratosthenes

Activities

 * 1) Review MathsIsFun: Prime and Composite Numbers. Create a list of prime numbers less than 100.
 * 2) Review MathsIsFun: Prime Numbers Chart and Calculator. Compare your list of prime numbers less than 100 for accuracy. Use the prime number calculator to find a prime number greater than 1000.
 * 3) Review  Generating primes and ExtendOffice: How to Generate Prime Numbers in Excel. Use Excel to create your own prime number generator.
 * 4) Review  Generating primes and /Prime number generators/. Write your own program to generate prime numbers.

Resources

 * /Prime number generators/