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

The  Prime pyramid with startvalue 0  is based on the counterclockwise  Ulam spiral  with  startvalue 0. 
The natural numbers in the  Prime pyramid  are placed only in the south quadrant of the Cartesian coordinate system.

Just like with the  Ulam spiral  the  Prime pyramid  has several  families of functions.
However the   families of functions  are less distinct (see below).


Miscellaneous: Prime pyramid   in a Cartesian coordinate system