1, 2, 3, 4, 5. And we want to have exactly three heads. And I'm going to call those three heads, I'm going to call them, let me do it in pink, heads A, heads B, heads C, just to give them a name. Although what we're going to see later in this video is that we don't want to differentiate between them. To us, it makes no difference if we get this ordering, heads A, heads B, heads C, tails, tails, or if we get this ordering, heads A, heads C, or heads B, tails, tails. We can't count these as two different orderings. We can only count this as one.