Is this number prime or composite - 1111.....1 (77 1's)
Note: Provide the explanation...
it is a prime number
Prime number 31 can be expressed in the form n^5 -1, where n=2. Are there any other primes that can be expressed this way?
How many ways can you find to make the number 10, by adding or subtracting prime numbers? The same numbers but in a different order count as the same answer. (Prime numbers are only divisible by themselves and 1 so they are 2, 3, 5, 7, 11, 13, ...)
