Multiply any two or more prime numbers then add 1. This should result in a prime number. Most times it will give you a prime but sometimes it will not work.
Does work: 2 * 11 + 1 = 23
Doesn't work = 3 * 3 + 1 = 10
Real World Application
Jim wants to program a computer program. but he needs to use an algorithm to in crypt the program. He wants to use an infinite number of primes, so he would use Euclidean principles.