Simple Math "Progression" - Need Smart People Help

Hello Everyone,

Thanks for viewing this and hopefully helping me out with this problem...

I'm writing a report on roulette and I need help figuring out a betting progression.

The minimum bet is $5, and the maximum bet is $500.

The "Martingale" theory is doubling your bet (playing black or red) until you win. However, I need a more mathematically correct betting progression.

So the question is, what betting progressions can survive 8 or more spins?

Here is an example of one betting progression that lasts 8 spins but does not hit the $500 limit (the next bet would be above the limit), and does not yield a profit, only breaks even)

$5

$5

$10

$20

$50

$100

$200

$400

The main progression I am looking for is the one that lasts 8 spins, and yields the highest profit!

Thank you so much to whoever can figure this out for me, as I'm absolutely horrible at math!

Thank you!