This is seriously weird.
https://www.quantamagazine.org/mathematicians-discover-prime-conspiracy-20160313/
"Two mathematicians have uncovered a simple, previously unnoticed property of prime numbers — those numbers that are divisible only by 1 and themselves. Prime numbers, it seems, have decided preferences about the final digits of the primes that immediately follow them."
https://www.quantamagazine.org/mathematicians-discover-prime-conspiracy-20160313/
"Two mathematicians have uncovered a simple, previously unnoticed property of prime numbers — those numbers that are divisible only by 1 and themselves. Prime numbers, it seems, have decided preferences about the final digits of the primes that immediately follow them."