I'm looking for finding frequent itemsets in sequences, which means the order of appearance of items matters in itemsets. Consider the following example :

1,2,3

1,3,2

3,1,2

Assume that the order of items matters, then if we put min_support = 3, {1,2} is frequent, because support({1,2})= 3 and every time we see {1,2} in this dataset, 2 comes after 1.

Let's consider {1,3}, we know that this itemset appears 3 times in our dataset, but is not frequent, because only in 2 transactions 3 comes after 1.

I'm looking for an algorithm that can do this for me, I found algorithms like GSP which do something similar to what i want, but they don't do exactly what i wanted to do. Can you please recommend me an algorithm which is able to find such frequent itemsets?

Thanks in advance