Dejan's System

True randomness is repeating in nature

Animation showing usage of Dejan's system in roulette

Dejan's System is an intriguing and relatively modern roulette system.

The system involves pre-selecting 12 numbers of your choice and assigning them the following bet ratio:

Numbers 1 2 3 4 5 6 7 8 9 10 11 12
Bet Ratio $1 $1 $1 $1 $2 $2 $2 $2 $4 $4 $8 $8

The 12 selected numbers can be any numbers of your choice. I've just used the numbers 1 to 12 for illustration purposes.

The bets can also be any size as long as they follow the same ratio as above.

You bet across all of your selected numbers on every spin using the corresponding bet ratio.

So in this basic example, each spin of the wheel would create a total bet amount of $36.

The system then works as follows:

So in other words, if you win with any of the four numbers in the top two highest bet ratios, you double the bet and keep playing in the hope that the hot streak will continue. This is what makes it a positive progression system, as you're increasing your bets when you win.

You then keep playing with the increased bet sizes until you lose, at which point you return back to the original bet ratio. But if you hit one of the top four numbers again, you double the bet size again too.

So if you hit a lucky streak, you'll make a massive return in a short period of time.

Dejan's System diagram

If you hit the table limit, keep playing at the current bet sizes until you lose.


Using Dejan's System, I start by selecting the following 12 numbers and assigning them the following bet sizes:

Numbers 8 27 14 11 2 35 25 12 9 32 19 21
Bet Sizes $1 $1 $1 $1 $2 $2 $2 $2 $4 $4 $8 $8

So my total wager by betting across all of these numbers is going to start out at $36.

Spin 1

The result of the first spin is 14 (win).

I've bet $36 in total and got $36 back (as I bet $1 on the number 14, and a single number win returns 35-to-1). So I basically get my money back and my balance remains the same.

This is a winning number within my first 8 selected numbers though, so I just repeat the same bet sizes on the next spin.

Spin 2

Numbers 8 27 14 11 2 35 25 12 9 32 19 21
Bet Sizes $1 $1 $1 $1 $2 $2 $2 $2 $4 $4 $8 $8

The result is 32 (win).

I win bigger this time, as I wagered $4 on the number 32.

This time I hit a number that's in the last 4 of my selected numbers (one that's within the two highest straight bets), so for the next spin I'm going to double the size of my bets.

Spin 3

Numbers 8 27 14 11 2 35 25 12 9 32 19 21
Bet Sizes $2 $2 $2 $2 $4 $4 $4 $4 $8 $8 $16 $16

The result is 8 (win).

I've hit a winning number again, but this is not a number that I double my bets on, so I'll just repeat the same bet on the next spin.

Spin 4

Numbers 8 27 14 11 2 35 25 12 9 32 19 21
Bet Sizes $2 $2 $2 $2 $4 $4 $4 $4 $8 $8 $16 $16

The result is 21 (win).

I seem to be getting very lucky in this imaginary example.

Anyway, this is another bet-doubling win for me, so I'll double my bet for the next spin.

Spin 5

Numbers 8 27 14 11 2 35 25 12 9 32 19 21
Bet Sizes $4 $4 $4 $4 $8 $8 $8 $8 $16 $16 $32 $32

The result of the next spin is 5 (lose).

I've lost (finally), so for the next spin I return back to my starting bet sizes and start over again.

Spin 6

Numbers 8 27 14 11 2 35 25 12 9 32 19 21
Bet Sizes $1 $1 $1 $1 $2 $2 $2 $2 $4 $4 $8 $8

The result is 4 (lose).

I've lost again. However, I'm already at my starting bet sizes, so I'll just keep the bets the same size until I start winning again…

There is no defined "end point" to this system. So you just keep playing it until you reach your target or decide to stop.


These numbers are not editable. In the actual system you can choose your own numbers on the wheel. I've set these as the numbers 1 to 12 for simplicity, as the results will be the same no matter what numbers you select.

The chart for Dejan's System is characterized by a general downward trend punctuated by the occasional massive win.

Over shorter sessions it can sometimes appear to work well, but if you increase the number of spins (e.g 5000) and keep repeating the simulation you'll see that the overall losses clearly far outweigh the wins.

You'll also frequently run out of money if you haven't got a large enough bankroll to absorb the losses before a big potential win.

So over the short term there's a chance you'll get lucky and feel like the system works. But over the long run you're losing money.

This system is similar to the Paroli system, but is more elaborate and without a progression limit.

Algorithm / Code

Here's some working Ruby code that shows how Dejan's system works from a programming perspective.

# Settings
balance = 1000
spins = 10

# Choose your own set of 12 numbers to use
numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]

# Assign bet ratios for these 12 numbers
ratios_initial = [1, 1, 1, 1, 2, 2, 2, 2, 4, 4, 8, 8]

# Create a copy of the ratios so they can be updated during play depending on if we win/lose
ratios_current = ratios_initial

# Repeat for a given number of spins
spins.times do |i|

  # Calculate the total size of the bet
  bet_total = ratios_current.sum
  # Update the balance to remove the total inital bet
  balance = balance - bet_total

  # Spin the roulette wheel
  result = rand(0..36)

  # Check if the result is a win
  win = numbers.include? result
  # Win
  if win
   # Get the index number of the winning number
   index = numbers.find_index(result)
   # Get the bet size of the number that won
   bet_size = ratios_current[index]
   # Calculate the winnings for hitting that number
   winnings = bet_size * 36
   # Update the balance
   balance = balance + winnings
   # If the index number of the winning number is in the last 4 of the selected numbers
   if (index == 8 || index == 9 || index == 10 || index == 11)
    # Double the bets
    ratios_current = {|x| x * 2}
  # Lose
   # Reset the bet ratios to the original starting bet ratios
   ratios_current = ratios_initial
  puts balance

  i = i + 1

Who invented this system?

This system was invented by a Serbian man named Dejan in 2022. So it's a relatively modern system.

They had lifelong experience with gambling, had a degree in Psychology, and worked as a dealer in a casino when they came up with the system.

Dejan started gambling at the age of 14 and was addicted to gambling up until the age of 32. Dejan was not a famous gambler or mathematician, but a regular guy that came up with their own unique system, just like many of us have done.

Despite having understood the statistics of gambling and how all systems are fundamentally doomed to failure, this was the final system Dejan believed could still work before they beat their gambling addiction.

The problem is I still have one system on my mind. It tortures me, I know theoretically it should be losing, but I read somewhere that, paraphrasing, "true randomness is repeating in nature", and it keeps creeping in every now and then, especially because I tried it online a few times some years ago, won every time (one time made 15k with $100, but lost it all not following the system but playing stupid big bets).

This page serves as proof that the system does not work, and that any system you create, no matter how convincing the logic behind it, is always going to lose in the long run.

What is the logic behind the system?

The system is designed based on the following belief:

"True randomness is repeating in nature."

The central concept of this system is that true randomness involves repeating sequences.

This system therefore attempts to exploit and profit from the repeating sequences that will inevitably occur within true randomness, such as what is produced via the roulette wheel.

Why is the system flawed?

The belief is that "randomness is repeating". However, in reality, "randomness is random".

Whilst it's inevitable that true randomness will contain repeating sequences of numbers, there is no reason why true randomness will repeat on specific numbers you have chosen.

In other words, it's equally likely that randomly generated numbers will produce repeating sequences on numbers you have not chosen as they are on numbers that you have chosen. As a result, the losses will always outweigh any "hot streaks" of repeating sequences on numbers that you have selected.

Because if repetition occurs within true randomness, it's going to repeat in a way you don't want it to as well.

This system fundamentally relies on randomness favouring specific numbers you have chosen over the long run, which is ultimately the opposite of randomness.


The most interesting aspect of Dejan's System is that it illustrates the common feeling within gambling addiction that there might just be that "one more system".

It's easy to accept that popular systems like the Martingale or Fibonacci are flawed as they have been widely disproven over time. But when you come up with your own system, it's tempting to believe that it may work as there's no literature out there to explicitly disprove it.

It can be a painfully tempting itch that you desperately want to scratch.

But the only remedy is the acceptance that the mathematics of roulette never change, and there is no system that will ever overcome the fundamental house edge built in to the game. Every possible system you can conceive is ultimately just a unique pathway to the same destination of losing money.

Nonetheless, this system is a testament to the fact that even if you have been addicted to gambling all of your adult life, there's nothing to stop you from working your way out of it, just like Dejan did.