An important fact about probabilities - there is always "a" chance, sort of like having a deck of 52 cards. While the odds you draw a 2 are one in 13 and that it's the 2 of Spades is 1 in 52, the chance that it is the next card you draw is equal to the chance that you draw any other card... all draws have a 1:52 probability and hence equal chance for any combination.
Maybe black listing specific options would be a good idea or setting up some regular expression filtering would be better.
An important fact about probabilities - there is always "a" chance, sort of like having a deck of 52 cards. While the odds you draw a 2 are one in 13 and that it's the 2 of Spades is 1 in 52, the chance that it is the next card you draw is equal to the chance that you draw any other card... all draws have a 1:52 probability and hence equal chance for any combination.
Maybe black listing specific options would be a good idea or setting up some regular expression filtering would be better.