Regarding the article below, it was mentioned that prime numbers can only end with digits 1,3,7 or 9 (except for 2 and 5) but that the frequency of that these digits occur are not random, as can be seen from the fact that it is unlikely that the same digit will occur twice for consecutive prime numbers. However the article also mentions that as the prime number tends to infinity, then the distribution of prime numbers also tends to become random. If it is true then how do we prove this fact and can we conclude that the distribution of primes is random or whether it is not random and there is in fact a pattern to it? 

<http://www.independent.co.uk/news/science/maths-experts-stunned-as-they-crack-a-pattern-for-prime-numbers-a6933156.html>