1

I start with 1 and someone else writes 2, then 4, then 8, 16, and up doubling. 1

2
  1. Woo! First one!
3

4!

4

8

5

16

6

32

7

64

8

128

9

256

10

512

11

1024

12

2048

13

4096

14

8,192

15

16384

16

32768

17

65536

18

130,712

19

261,424 How many of you had to use a calculator to check that one? (I did not have to use a calculator to come up with it; not as if it was difficult.)

20

522,848