The (double) Primorial sieve  &  Prime spirals E-mail

The picture shows the distribution of  prime numbers over the base of the  third Primorial sieve.
Prime numbers > p3  (with p3 = 5)  are only found above the  eight  struts of the  third Primorial Sieve.
The struts are co-prime to the prime numbers  {2, 3, 5}  of the  third primorial.

There are infinite many  double Primorial sieves,  each built from the previous sieve, see the  (double) primorial sieve.pdf   
The ratio of  struts  in the  base  of the sieve decreases with every larger Primorial sieve.
The  forth (double) Primorial sieve  is the first sieve with  ALL  the properties of the  (double) Primorial sieves.
The  ninth (double) Primorial sieve  is the last sieve where  4 byte Integers  suffices to load the values of the  struts  of the  base  into memory.


Double Primorial Sieve: Picture of the third (double) Primorial sieve