The point of the graph are: (1,1),(2,2), (3,4), (4,8).
Then the sequence is:
For the x-coordinate:1,2,3,4,5,6,7...
For the y-coordinate:1,2,4,8, which is 2^0,2^1,2^2,2^3... so there for the next y-coordinates are 16,32,64,128, ...
So the sequence is: 1,2,4,8,16,32,... 2^x.