Fermat number [SEP] named after
Fermat number
In mathematics a Fermat number, named after Pierre de Fermat who first studied them, is a positive integer of the form
where "n" is a nonnegative integer. The first few Fermat numbers are:
If 2 + 1 is prime, and "k"  0, it can be shown that "k" must be a power of two. (If "k" = "ab" where 1 ≤ "a", "b" ≤ "k" and "b"
Baillie–PSW primality test
The Baillie–PSW primality test is a probabilistic primality testing algorithm that determines whether a number is composite or is a probable prime. It is named after Robert Baillie, Carl Pomerance, John Selfridge, and Samuel Wagstaff.
The Baillie-PSW test is a combination of a strong Fermat probable prime test to base 2 and a strong Lucas probable prime test. The Fermat and Lucas test each have their own list of pseudoprimes, that is, composite numbers that pass the test. For example