This is a betting system most often employed on even money bets in roulette.
The Whittacker Progression System is somewhat similar to the Labouchere:
The difference being, that you build up your sequence in a different way: in the Labouchere the first and the last bets on a loss run are summed (and crossed off in the case of a win), with the Whittacker you sum the last 2 unsuccessful bets. This gives you a more rapid claw back of losses when you win.
The main plus side of the Whittaker as compared to the Labouchere is that the negative swings are generally less harsh. Always start your Whittaker with a 1 unit bet.
Let’s look at an example:
Bet 1 unit, and 1 unit again if you win
Bet 2 units and 1 unit again if you win, or 3 units if you lose again (1+2=3)
Bet 3 units and 1 unit again if you win, or bet 5 is you lose (3+2)
Bet 5 units, and 2 units if you win, or 5+3=8 units if you lose
Strike off the 2 last lost bets in your sequence if you win and add the last 2 bets to get the next number in your progression if you lose. You get our drift.