Useful calc links:

If are interested in algorithms for finding very large primes:

The tutorial on how to find a new largest known prime goes into detail about the above mentioned Amdahl 6 lucas.cal method.

If are interested the product of curious primes:

Calc is free

Calc is open software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation version 2.1 of the License.

Many people have expressed their thanks the many people who wrote calc, tested calc, contributed code to calc, patched calc, and helped to improve it since it started back in 1984.

We, the authors of calc wrote calc because they wanted to write it, because it was fun writing it, and because we wanted you to use and enjoy it.

If you use and enjoy calc, and you want to show your appreciation for calc, you might consider doing some of the following: