So I often see this type of question appear: how many primes are there between 9! + 2 and 9! + 8. The answer is none because 9! = 9*8*7.... *2*1, since 9! is a multiple of 2, adding 2 means it's still a multiple of 2 and hence not prime. However, if the question were to ask, 9! + 12, this is also 9! + 5 + 7, so does this mean this is also not prime? So to generalize, can we say there are no primes between 9! + 1 to 9! + (9+8+7.....+ 2+1)?