You will find the probability of getting a single such a number is D/N = 6/55 , therefore the probability of getting such numbers six times in a row is = (6/55)6. Which is at around ~0,00000168.
Which means you have an about ~1 in 600k chance but its still possible.
Your math is wrong.
You have odds of 6/55 when drawing the first number only. Since the numbers drawn are not returned to the pool and cannot be drawn a second time, then after you have drawn the first number there are no longer 6 possibilities you can choose, but 5. Similarly, there are not 55 balls to choose from, but 54. So the odds for the second ball are not 6/55, but 5/54. The same logic applies for all future balls. So instead of (6/55)
6, the actual equation will be (6/55)*(5/54)*(4/53)*(3/52)*(2/51)*(1/50). So the odds are ~1 in 29 million.
See my earlier post in this thread for a full explanation:
https://bitcointalksearch.org/topic/m.61047255And this is the explanation of one an OCTA Research on the probability
The last paragraph of the image you have shared sums it up nicely. If we were seeing 433 winners on a truly random selection of balls, then that would be evidence of something gone wrong or some foul play. But we are not seeing that. Instead, we are seeing 433 winners on a very obvious pattern which has been selected more than average simply by virtue of it being a very obvious pattern.