Are you trying to get the Y by placing X?
If so, the following can get you the result:

function g(x : number)
return math.pow(0.5,x)
end

Every X you write will give you the Y

If you’re referring to the decreasing intervals between each tick, I suppose you can put the result of g(x) in task.wait().
For example:

function g(x : number)
return math.pow(0.5,x)
end
local startX = 1
local endX = 8
local interval = 0.1
for x = startX, endX, interval do
task.wait(g(x))
print("interval")
end