fermat_factor, a Python code which uses Fermat's factorization method to decompose an integer N into the product of two factors, N = A^2-B^2 = (A+B)*(A-B).
The algorithm seeks to write N = A^2 - B^2 = ( A + B ) * ( A - B ).
The information on this web page is distributed under the MIT license.
fermat_factor is available in a C version and a C++ version and a Fortran90 version and a MATLAB version and an Octave version and a Python version.
is_prime, a Python code which determines if a given integer n is prime, using various versions of the sieve of Eratosthenes.
lucas_lehmer, a Python code which determines whether a Mersenne number 2^n-1 is prime by applying the Lucas-Lehmer test.
prime_factors, a Python code which returns a list of the prime factors of an integer.
prime_fermat, a Python code which applies Fermat's primality test to an integer n, which always correctly identifies primes, but sometimes also accepts nonprimes. Nonetheless, the test is useful for weeding out most nonprimes. The accuracy of the test can be improved by running it for several bases.
prime_pi, a Python code which evaluates Pi(n), the number of primes less than or equal to an integer n.
prime_plot, a Python code which displays a box plot of the prime and composite numbers.