Hello I have a question.
Can I set up a strategy for playing roulette where I bet on red and black at the same time in differing values depending on the last 9 rolls?
Red and black at the same time?
Generally yes. Depending on the special needs.
The function optimize chances calculates the differential bet, if you mean this.
The roulette strategy Differential d’Alembert works with this concept.
First of all it is never a good idea to bet opposite chances at the same time.
Don't bet red and black, odd and even and all corresponding other combinations.
Usually the progression is more important than the chance.
On the long run, you need to have a lot of money, to cover loss streaks of your progression.
Don't bet red and black, odd and even and so on.
If you do that, you bet 36 (2x 18) numbers out of 37.
All time you bet 1 unit on red and 1 unit on black, you get 2 units back all the time, as long as Zero is not coming. You don't win anything.
When Zero comes, then your 2 units are lost (depending on zero handling).