
Prime-generating fractions - lesterbuck
http://www.johndcook.com/blog/2013/10/12/prime-generating-fractions/
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pontifier
The way this is constructed is interesting, but it doesn't appear that a real
sequence to generate primes is required, just a list of them:

D=0

SUM=0

for n:

    
    
      D += num_digits(PRIME[N]) // +1 for a nice single 0 between them
    
      SUM += PRIME[n]/(10^D)
    
      print fraction(SUM)

~~~
svnfv
This method results in much shorter numerators and denominators than the list
of primes it generates. Simplifying this fraction only chops off 2 or so
digits on average.

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abecedarius
From the title I expected
[http://en.wikipedia.org/wiki/FRACTRAN](http://en.wikipedia.org/wiki/FRACTRAN)
(see the list of fractions at the top).

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mathattack
It borrows one problem from Project Euler and seems to scream for another.

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yeukhon
Okay. Very interesting. For those who don't understand like me, what is the
technical use of this? Where will this be used? Are we somehow going to use
this in cryptography?

~~~
inglesp
I don't think it does have a technical use. You certainly couldn't use this
technique to generate new primes, since the fractions have been deliberately
chosen based on the primes they will generate.

As it stands, it's just a fun mathematical curiosity.

