# Prime Numbers TrueFalse Prime Numbers TrueFalse Prime Numbers

Prime Numbers – True/False

Prime Numbers – True/False

Prime Numbers – True/False

Prime Numbers – True/False 3. There is no end to the prime numbers. True We can prove this by assuming there is a fixed number: Multiply all the primes together, then add 1. This number doesn’t divide by any of the primes, but all numbers greater than 1 either are prime or divide by primes. So this number either divides by primes we didn’t use, or is itself a prime we didn’t use. But we used them all!

Prime Numbers – True/False 4. There is no end to primes only 2 apart (eg 17 & 19). (We’ve found the first 808, 675, 888, 577, 436 of them, but we did it the long way) Unknown This idea is called the ‘twin primes conjecture’. Many mathematicians think it’s true (and even that there an infinite number of primes 4 apart, 6 apart, 8 apart, etc) but we haven’t been able to prove it yet.

Prime Numbers – True/False

Prime Numbers – True/False

Prime Numbers – True/False

Prime Numbers – True/False 8. $100, 000 was offered to factorise a 309 digit number. True RSA encryption is based on the difficulty of factorising large numbers. Two large primes are multiplied together to produce a ‘key’ meaning anyone can encrypt data to send to you, but only you - the person who generated the key - can decrypt it. The only known way to break the code is to split the key into its prime factors.

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