The 31 System
The 31 system is an older system which requires up to 31 units to be wagered.  It is a
betting progression with a twist.  First the betting sequence: 1, 1, 1, 2, 2, 4, 4, 8, 8.  
Total them up and you have 31 units, hence the source of the name.  

Start by betting one unit.  If you win, continue to bet one unit.  Once you lose the one
unit bet, go to the second bet of the sequence.  If you continue to lose, continue
through the sequence.  Once you win, double the bet you just won.  This is the twist.  
If you win this bet, you start the sequence over with the first bet (one unit). If you lose
this bet, however, go up to the next bet in the sequence.  Should you advance to the
last 8 unit bet, and haven't won the double up bet, you have lost 31 units.  At this
point, start over, or go play something else.

The  31 system is a negative progression, with flat betting when winning, except for
the one double up bet.  To lose the 31 units, you would have to lose nine bets in a
row, or only win one bet out of ten.  If you're having luck like this, it's probably time to
hit the buffet or bar.  Long streaks of losses can and do occur, and probably more
often in a game like Roulette than Blackjack.  Still, this system is relatively safe when
carried to it's end.  The most you can lose is 31 units.  Unlike the Martingale, you limit
the number of increases to nine losses, but you progress your bets much more slowly.
You have to hope you have two wins in a row to complete the recovery of your
previous losses.  If you don't, you will lose the 31 units.

Try it before you buy it.  In other words, practice it, and any system for that matter, at
home for free before you purchase 31 units worth of chips.
Average Joe Roulette
The Roulette Systems Authority
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