Primes & Probable Primes

This is a very brief introduction, as I have only recently started work on searching for primes and probable primes amongst particular types of number constructed using familiar integer functions such as factorials and primorials.

Interesting Primes and Probable Primes looks at a variety of constructs, most of which are very familiar, such as factoprimorials, stretching the definitions to include new combinations involving 2-factorials.

Multifactorial Pseudoprimes takes as a starting point the 2-factorial and looks at various deviations that preserve the built-in sieve arising from the Chinese Remainder Theorem.

Multifactorial Combinations looks at combining multifactorials of the same modulus to obtain further sequences hopefully rich in primes and probable primes.

Probable co-primes looks at cofactors when multifactorials are divided by an exact known divisor.

More Primes from the Factorials considers multifactorials with one small divisor, leading to very specific forms for some primes.


Removing the Restrictions considers loosening some of the restrictions applied previously to provide additional probable primes from the multifactorials.


Complex Multfifactorials considers multiplicative sequences of descending positive integers based on more complex sequences.


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