On Dec 25, 1:03 pm, Frogwatch wrote:
A great time waster is this web site:

http://www.numberspiral.com/

for generating spirals rich in prime numbers.

Now, when primes are plotted on a 1-D array, ie., a number line, no
patterns emerge. However, wehn we plot them on a 2-D array we see the
sorts of patters seen on these spirals and on the Ulam spiral. What
happens if we find a way to plot them on a 3-D array?

I prefer the Ulam spiral to the Sack's spiral because from anywhere on
the Ulam spiral if it is unlabelled, you cannot tell if it has an
origin. On the Sack's spiral, all the arcs can be traced back to the
origin.
I have not yet figured out a way to plot prime numbers in a volumetric
filling way.