ANY prime number p greater than 3 can be expressed as p=6n+1 or p=6n+5 (p=6n-1), where n is an integer >1.
That's because any prime numberp greater than 3 when divided by 6 can only give remainder of 1 or 5 (remainder can not be 2 or 4 as in this casep would be even and remainder can not be 3 as in this casep would be divisible by3).
But:
Note that, not all number which yield a remainder of 1 or 5 upon division by 6 are primes , so vise-versa of above property is not correct. For example
...
That's because any prime numberp greater than 3 when divided by 6 can only give remainder of 1 or 5 (remainder can not be 2 or 4 as in this casep would be even and remainder can not be 3 as in this casep would be divisible by3).
But:
Note that, not all number which yield a remainder of 1 or 5 upon division by 6 are primes , so vise-versa of above property is not correct. For example
...
