1, 2, 4, 12, 48

1 x 2 =2
2 x 2 =4
4 x 3 =12
12x4 =48

1 (2) 2 (2) 4 (3) 12 (4) 48

1 x 1 =2
2 x 2 =4
4 x 3 =12
12x4 =48

Multiply by 1, 2, 3, 4, then the next would be 5


That's originally what I thought but 1x1=1