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

September 2019:
The  Modulo primality test  is based on the  prime spiral with one segment. Each natural number is member of the Eastward family of quadratic polynomials with only two terms.
By way of modular arithmetic the number of digits is reduced when checking a large integer for a possible divisor.
The final product of  Modulo primality test.pdf  was completed september 2019.

Augustus 2018:
The four segments of the Ulam spiral in a Cartesian coordinate system are taken apart. New prime spirals are drawn up with just one, two or three segements. This led to prime spirals with infinitely many segments.
The final product of  the segmented prime spirals.pdf   was completed mid 2018.

May 2017:
In 2013 preliminary results of the   (double) primorial sieve.pdf   gave an opening to unravel the Ulam spiral and the opportunity to test the usefulness of the (double) primorial sieve.
The final product of  the unraveling of the Ulam spiral.pdf   was completed mid 2016.

January 2012:
The domainname "www.primorial-sieve.com" was registered and activated .

Late 2011:

The software was developed for both the Primorial sieve and the double Primorial sieve.
Both programs where integrated into one, since the double primorial sieve uses the same large primorial sieve.

Beginning of 2011:
A draft paper with the full description of the (double) primorial sieve was officially registered.

A prime number was placed on the short side of a primitive Pythagorean triangle, which ultimately led to the definition of the (double) primorial sieve.


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