--How to use it? Press start to start the calculations. It does find a lot of prime numbers in the first minutes of calculating. It will get slower as more calculations will be needed. I recognised that this is not the fastest method of calculating prime numbers, but you can barely notice it. I am stil working on it to optimalize the programm. --What does this program do? This program is for calculating prime numbers. The code starts with 2, then 3, 5, 7, 11 and so on. It will then divide each odd number by all numbers in front of it, and check if it is an integer. If it is, it will go on to the next odd number because it can be divided. If it is a prime number, it can only be divided by one and itself, and it will be set to the highest prime number you calculated so far. You also can enter a number and the programm will check if it is prime or not, and you can show the list of all prime numbers you have calculated so far.
An even faster remix, thanks to @mdgabbert 's improved version! Much thanks!