To compute the first primes click on the Compute primes button
If you change the default number of primes click again on the Compute primes button to update the array of primes. If the number of searched primes is important it may take a few seconds to get the result of the computation.
The same method allows to compute the twin primes, that is consecutive primes distant of 2. For example, 11 and 13 are twin primes. The number p2(x) of twin primes less than x and the computation of Brun's constant (that is the sum of the inverse of the twin primes) are also given at the end of the file. To find p2(x) for large values of x (say up to 1015 or more), note that most algorithms are variants of Eratosthenes' sieve.
To compute the first twin primes click on the Compute twin primes button
If you change the default number of twin primes click on the Compute twin primes button to update the array of twin primes.