THINGS TO KNOW ABOUT PRIME NUMBERS:
(courtesy of factmonster.com: View Website)
- The only even prime number is 2. All other even numbers can be divided by 2.
- If the sum of a number's digits is a multiple of 3, that number can be divided by 3.
- No prime number greater than 5 ends in a 5. Any number greater than 5 that ends in a 5 can be divided by 5.
- Zero and 1 are not considered prime numbers.
- Except for 0 and 1, a number is either a prime number or a composite number. A composite number is defined as any number, greater than 1, that is not prime.
To find out if a number is prime or not, you should try dividing it by 2, and see if you get a whole number. If you do, then it is not a prime number. If you don't get a whole number, next try dividing it by prime numbers: 3, 5, 7, 11 (9 is divisible by 3) and so on, always dividing by a prime number.
Polarization is a term used to describe what happens to light as it travels through a filter.
In this case, polarization is the process of filtering the data set to get a subset containing only the ones with a certain characteristic.
If we filter those numbers to a set with the characteristic of having modulus 3 equal to 1 you have the set 1, 4,7 ., and 10