Ex-News JunkieArchimedes Spiral and Prime NumbersSun Aug 6, 2017 7:23pm2001:1970:5c22:6100:94f1:f44a:ea72:3adaBelow is a plot of 32,000 prime numbers on an Archimedes Spiral. In the first plot it just looks like an onion. In the second plot I hid the lines joining the points. All the points are prime numbers in polar coordinates. All 32,000 primes line up on one of the radial spokes. Apparently prime numbers are not entirely random, but are in fact a periodic function. I think it's neat-o.

Did you know ... — Mondo Fuego™ , Mon Aug 14 5:26am... the sum of the digits of a prime number is a prime number? It's the easy way to tell if a number is a prime number. I just discovered this little-known fact on my own, although I am quite sure... more

Is 49 a prime number? (nm) — Ex-News Junkie, Tue Aug 15 8:28pm

No, it is 7 squared (nm) — jb, Tue Aug 22 2:17pm Drum roll — Ex-News Junkie, Tue Aug 8 3:19pmNot sure about the notation, but here goes: The set of all prime numbers P is a subset of SP: SP = {2,3,5, and R + n x 360}, for n = {0,1,2,3,... } where R = { 1,7,11,13,17,19,23,29,... more

Another variation — Ex-News Junkie, Tue Aug 8 7:31pmAll prime numbers P are a subset of SP = {2,3,5, and R + n x 30} where R = {1,7,11,13,17,19,23,29} n = {0,1,2,3,... } P is prime if (P mod SP) 0 It's simpler I suppose, but it loses the perspective... more

It's just a coincidence — Ex-News Junkie, Sat Aug 19 9:31pmIf you write the numbers out from 1 to 30, then cross out all the even numbers, then cross out any number that is divisible by 3,5,7 or 9, what remains are the root angles. You can plot the result in ... more