Re: [math-fun] What use are primes?

At 08:13 PM 4/12/2006, Stan E. Isaacs wrote:

I had a student in my computer class ask me a mathematics question: she asked what was the use of prime numbers?

One thing is that there are several functions such that if you know their value on primes and powers of primes, you can easily compute the function on composite numbers. Stated another way, if you can factor a composite number into its prime factors, then it is easy to compute the function.