Primes that are the concatenation of the first "n" primes written in decimal. Any finite collection of divisibility events associated to distinct primes is mutually independent. In the case of squares of primes, those divisors are formula 5. Its prime elements are known as Gaussian primes. Let denote the number of primes in the arithmetic progression less than . He proved that the sum of the reciprocals of the primes diverges. By itself, this makes it easy to prove the primality of the known Fermat primes. There are also conjectures and unsolved problems about the Gaussian primes. It is one of only four known double Mersenne primes. Many fundamental questions about Mersenne primes remain unresolved. This algorithm produces all primes not greater than . The last seventeen record primes were Mersenne primes. There are several probabilistic arguments for the finitude of Fermat primes. This is often the case for fast primes and wide-angle lenses. The cameras were lensed with Leica Summilux-C or Zeiss Master Primes.