In mathematics, 19 is significant as it is a Lucas prime, which is a prime number that can be expressed in the form L(n) = 2^(n) - 1, where n is a non-negative integer.
It is the eighth prime number and a member of a twin prime pair with 17, which are two primes that differ by 2. The number 19 is a prime number, meaning it is only divisible by 1 and itself.
