“…For several years, a wide range of applications in various domains have benefited from KDD techniques and many work has been conducted on this topic. The problem of mining frequent itemsets arose first as a sub-problem of mining association rules [1], but it then turned out to be present in a variety of problems [24]: mining sequential patterns [3], episodes [32], association rules [2], correlations [12,43], multi-dimensional patterns [26,28], maximal itemsets [7,54,29], closed itemsets [47,37,38,41]. Since the complexity of this problem is exponential in the size of the binary database input relation and since this relation has to be scanned several times during the process, efficient algorithms for mining frequent itemsets are required.…”