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**orange gold** Ahhh! It doesn't work after the number 121.. And what I meant was the hundreds prime, not 100th prime. so I checked up to the number "103" ... anyways when I hit 121 I started realizing my pattern didn't work for things divisible by 11, and 13, and 15, etc. It was a neat pattern though.. What I was doing was squaring the number, taking the some of the digits that make up that number, and then took the sum again and kept doing it until I had a single digit number left and if that number was 9 than it wasn't prime. Other than that I only had to check if the number squared ended in 5, or if the number was divisible by 7. /:

My rule went as follows:

To get a list of primes:

Determine your range for the list of primes.

Get all the odd numbers in your range.

Divide all numbers by 7, any number that is evenly divisible is not prime, remove them.

Square all remaining numbers.

any number not ending in 1 or 9 is not prime, remove them.

Get the sum of the digits in a number for each number in your range, repeat this process till you have a one digit number.

(ie 15^2 = 225 --> 2+2+5 = 9

(ie 7^2 = 49 --> 4+9 = 13 --> 1+3 = 4)

Any number that has a sum of 9 is not prime, remove them. (with the 2 exceptions of the numbers: 3 & 5)

All remaining numbers ARE prime.

**This process will say that 1 is prime (which I consider as prime anyways.), 2 is not prime (which I don't consider as prime anyways.)

Pretty bummed right now, but I willn't give up /: