I Have to answer the game, "what's my rule" I've tried everything. I do not know if the teacher made a mistake in the problem.

When x=1, y=3
x=2, y=6
x=3,y=12
x=4, y=24

I see that Y is doubling, but I need a rule to use with variable

Thanks!

y = 3*2^(x-1)

or, y = 3/2 * 2^x