  LCM is an algorithm for enumeration of frequent closed itemsets in
transaction databases. It is well known that when we ignore the required
frequency, the closed itemsets are exactly intents of formal concepts in Formal
Concept Analysis (FCA). We describe LCM in terms of FCA and show that LCM is
basically the Close-by-One algorithm with multiple speed-up features for
processing sparse data. We analyze the speed-up features and compare them with
those of similar FCA algorithms, like FCbO and algorithms from the In-Close
family.
