There are \(19\) adventurers standing in a queue to see a dragon’s treasure. They can enter the cave in three groups, with \(15\) minute breaks between two consecutive groups. The order in which adventurers will enter the cave is fixed – they are in a queue after all. But they can still decide who will be in the first, second and third group. Each group has to consist of at least one adventurer. In how many ways can they do that?