A marching band is preparing to line up for a parade. They are trying to find an arrangement so that each row of performers has the same number. However: • When they line in groups of 2, there is 1 performer left out. • When they line in groups of 3, there are 2 performers left out. • When they line in groups of 4, there are 3 performers left out. • When they line in groups of 5, there are 4 performers left out. • When they line in groups of 6, there are 5 performers left out. Thankfully, when they line up groups of 7, there are no performers left out! What is the smallest possible number of performers in the group? Help me please.