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Been playing this pretty fun variant, couldn’t find a write up anywhere. Might not be able to get the exact house edge because there is a bonus wheel with percentages I haven’t been able to find.

You make 5 equal bets: 4 standard hands of blackjack and the mandatory 20s bet. The required side bet pays based on the number of 20s (hard or soft) that get dealt. The bet pays once cards are dealt. Hitting to 20 does not count, and outcome of the hands themselves don’t matter

1: spin a wheel of push , 1x 2x or 3x your bet

2: 4 to 1

3: 20 to 1

4: 420 to 1

One thing I like is even though it’s $25 per hand (a lot for me, especially when it’s just on a couch at home) you only need to win 3/5 spots to come out ahead and you don’t lose all 5 spots too often

I think you can play this game for free if you live in a state where online gaming is legal and you can download the draft kings app. Once you’re signed in, there is an info button on the logo and you can select demo.

I’ve mostly been playing basic strat, but was wondering if the mandatory side bet opens for some “free” doubles or splits you wouldn’t normally go with

Has anyone played this? I think it’s really a fun take on BJ

8 Decks, shuffled every round.

The wager on each hand and the four 20s sidebet must be identical. If you bet $5, $1 goes on each spot.

I didn't see anything egregious in their suggested strategy (under settings/paytable on the demo), but I didn't do a close review.

I didn't play enough rounds to get a good feel for the sidebet spinner weighting. Based on the graphics, my guess is that the spinner offers 6 fair stops, of push - 1x - push - 2x - push - 3x.

Quote:GBAMOne thing I like is even though it’s $25 per hand (a lot for me, especially when it’s just on a couch at home) you only need to win 3/5 spots to come out ahead and you don’t lose all 5 spots too often

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At least in the web demo version, the $5 table minimum is satisfied by a $1 bet on each spot, for $5 total per round.

Quote:DieterQuote:GBAMOne thing I like is even though it’s $25 per hand (a lot for me, especially when it’s just on a couch at home) you only need to win 3/5 spots to come out ahead and you don’t lose all 5 spots too often

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At least in the web demo version, the $5 table minimum is satisfied by a $1 bet on each spot, for $5 total per round.

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It is for the real money draft kings app too but I wanna win $2k lol

Anyone got the math on getting dealt 4 20s

Quote:GBAMQuote:DieterQuote:GBAMOne thing I like is even though it’s $25 per hand (a lot for me, especially when it’s just on a couch at home) you only need to win 3/5 spots to come out ahead and you don’t lose all 5 spots too often

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At least in the web demo version, the $5 table minimum is satisfied by a $1 bet on each spot, for $5 total per round.

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It is for the real money draft kings app too but I wanna win $2k lol

Anyone got the math on getting dealt 4 20s

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To get dealt 4 20's, the chance is about 1/7.8k, for infinite*** decks (if I worked it out right).

***: The game is played with 8 decks (going by posts above)

Note : I have played it in demo mode before, but I don't know the value for getting 1 20

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Update (About 10pm, Pac Time):

Quote:Dieter(snip)

I didn't play enough rounds to get a good feel for the sidebet spinner weighting. Based on the graphics, my guess is that the spinner offers 6 fair stops, of push - 1x - push - 2x - push - 3x.

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At the infinite deck level, I get a player edge of 2.43% for the bonus game (see figures below)

Chance / Odds / EV:

0 x 20 = 63.7325023584590000% / blank / - 63.73%

1 x 20 = 30.3890077470798000% / 1 to 1^^^ / +30.39%

2 x 20 = 5.4337960872262000% / 4 to 1 / +21.74%

3 x 20 = 0.4318248546140020% / 20 to 1 / +8.64%

4 x 20 = 0.0128689526209471% / 420 to 1 / +5.40%

Total EV = -63.73% + 30.39% + 21.74% + 8.64% + 5.4% = 2.43%

^^^: Assuming that the "spinner offers 6 fair stops, of push - 1x - push - 2x - push - 3x.". as stated in the "snipped quote", above.

Note: Again this is for infinite decks,

edit: I am notoriously bad at math.

Quote:DieterI estimate about 1 in 14500. This is not exact, it's an estimation.

edit: I am notoriously bad at math.

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I originally got that, but then I remembered that A-9 and 9-A, also count as a 20 for the "bonus".

Note: I played it about a week or two ago, so they may have changed the rules?

Quote:ksdjdjQuote:DieterI estimate about 1 in 14500. This is not exact, it's an estimation.

edit: I am notoriously bad at math.

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I originally got that, but then I remembered that A-9 and 9-A, also count as a 20 for the "bonus".

Note: I played it about a week or two ago, so they may have changed the rules?

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Well, I only played about 5 deals, and forgot entirely about soft 20.

I think that the odds are likely to favor the house. ;)

Quote:DieterQuote:ksdjdjQuote:DieterI estimate about 1 in 14500. This is not exact, it's an estimation.

edit: I am notoriously bad at math.

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I originally got that, but then I remembered that A-9 and 9-A, also count as a 20 for the "bonus".

Note: I played it about a week or two ago, so they may have changed the rules?

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Well, I only played about 5 deals, and forgot entirely about soft 20.

I think that the odds are likely to favor the house. ;)

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Probably, but I get a small player edge at infinite decks, if all pays are " to 1" for the bonus.

Note: I may be able to work out a more accurate chance and EV, but I am slower at doing it the "correct way for 8 decks" (compared to the infinite deck "short-cut estimate")

Quote:ksdjdj(snip)

4 x 20 = 0.0128689526209471% / 420 to 1 / +5.40%

(snip)

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For 8 decks, I get about 0.0114...% as the chance*** for "4 x 20".

***: I took some more short-cuts in getting this "8-deck" figure, because I didn't want to manually work out all the "16 ways you can get 4 x 20".

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Important Update (about 10:45 pm, Pac time):

Reminder, the "2.43% player edge" that I mentioned in previous replies, was for infinite deck only, the "8- deck edge" will almost surely be in the houses favor.

Quote:Dieter(snip)

I didn't play enough rounds to get a good feel for the sidebet spinner weighting (snip)

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Here are my results after making it to "20 x rounds of the sidebet spinner": .

Totals:

0 x 20 = ?

1 x 20 = 20***

2 x 20 = 2

3 x 20 = 0

4 x 20 = 0

***: Below is the break-downs for the "sidebet spinner"

Odds (to 1) / No. of times it occurred

Push / five

1 / nine

2 / three

3 / three

Note: The sample size is probably too small to work out a good estimate of the "sidebet spinner" weighting, but anyone can add my figures to their testing, if they choose to do so.

Quote:Dieter

edit: I am notoriously bad at math.

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I worked out the probability for four pat 20's off-the-top of an 8D shoe to be 7.967005 x 10^(-5), or about 1 in 12,550 rounds.

Hope this helps!

Dog Hand

Edit: fixed the mantissa to say 7.967005 rather than 0.7967005.

Totals:

0 x 20 = ?

1 x 20 = 40***

2 x 20 = 4

3 x 20 = 0

4 x 20 = 0

***: Below is the break-downs for the "sidebet spinner"

Odds (to 1) / No. of times it occurred

Push / eleven

1 / seventeen

2 / eight

3 / four

Note: The sample size is still probably too small to work out a good estimate of the "sidebet spinner" weighting, but anyone can add my figures to their testing, if they choose to do so.

Quote:DogHandQuote:Dieter

edit: I am notoriously bad at math.

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I worked out the probability for four pat 20's off-the-top of an 8D shoe to be 0.7967005 x 10^(-5), or about 1 in 12,550 rounds.

Hope this helps!

Dog Hand

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I saw a number like that too, but I didn't like it.

When I punch 1/(7.97*10^-6) into my calculator, I get an extra zero.

Care to smarten me up?

The paytables all state payouts as "to 1", but the software seems to display game results as "for 1". I understand why they do it, but it annoys me.

Turning off animations in the web version does speed the game, but not enough to make it engaging for me.

The side bet resolution really slows down the game.

If you think video poker on turbo "could be faster", you'll probably notice.

I'm glad the music can be disabled.

Objective notes:

Double after split is allowed. I had missed that.

No action allowed on hands totalling 21.

Quote:DieterQuote:DogHandQuote:Dieter

edit: I am notoriously bad at math.

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I worked out the probability for four pat 20's off-the-top of an 8D shoe to be 0.7967005 x 10^(-5), or about 1 in 12,550 rounds.

Hope this helps!

Dog Hand

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I saw a number like that too, but I didn't like it.

When I punch 1/(7.97*10^-6) into my calculator, I get an extra zero.

Care to smarten me up?

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Dieter,

Oops... I mistyped the mantissa. I should have typed 7.967005 x 10^(-5).

I shall edit my original post.

Dog Hand

Quote:DogHandOops... I mistyped the mantissa. I should have typed 7.967005 x 10^(-5).

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If catching a minor flub on a decimal place is the worst thing that happens until next year, I think things are pretty ok.

Does the 1/12550 approximation include soft hands?

Quote:DieterQuote:DogHandOops... I mistyped the mantissa. I should have typed 7.967005 x 10^(-5).

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If catching a minor flub on a decimal place is the worst thing that happens until next year, I think things are pretty ok.

Does the 1/12550 approximation include soft hands?

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Dieter,

Yes, I counted both hard and soft 20's. These are the probabilities for 4 H and 0 S, 3 H and 1 S, 2 H and 2 S, 1 H and 3 S, 0 H and 4 S, and their Sum, respectively:

6.87746E-05 9.54142E-06 1.20237E-06 1.37414E-07 1.42182E-08 7.967005E-05

Dog Hand

Quote:DogHandQuote:DieterQuote:DogHandOops... I mistyped the mantissa. I should have typed 7.967005 x 10^(-5).

link to original post

If catching a minor flub on a decimal place is the worst thing that happens until next year, I think things are pretty ok.

Does the 1/12550 approximation include soft hands?

link to original post

Dieter,

Yes, I counted both hard and soft 20's. These are the probabilities for 4 H and 0 S, 3 H and 1 S, 2 H and 2 S, 1 H and 3 S, 0 H and 4 S, and their Sum, respectively:

6.87746E-05 9.54142E-06 1.20237E-06 1.37414E-07 1.42182E-08 7.967005E-05

Dog Hand

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I got the same starting figures as you, but I did this (to get my estimate):

(6.87746E-05 x 1) + (9.54142E-06 x 4) + (1.20237E-06 x 6) + (1.37414E-07 x 4) + (1.42182E-08 x 1) = ~ 0.0001147...

Note: I don't know if the above step is needed for this kind of problem, but it is similar to what I do when I want to work out my "sports multi " estimated chances (see "three leg" example below):

Example: Say I bet on team A (50% chance of winning), B (60% chance of winning), and C (80% chance of winning) in a three leg multi and for whatever reason I wanted to know what the chances for winning 0 legs to all 3 legs is:

w = "chance of winning", l = "chance of losing"

0 legs = A l x B l x C l = 0.5 x 0.4 x 0.2 = 0.04

1 leg = (A l x B l x C w) + (A l x B w x C l) + (A w x B l x C l) = ... = 0.26

2 legs = (A l x B w x C w) + (A w x B l x C w) + (A w x B w x C l) = ... = 0.46

3 legs = A w x B w x C w = 0.5 x 0.6 x 0.8 = 0.24

4% + 26% + 46% + 24% = 100%

Note: The main reason I needed to know the above for sports, was because I used to get money back for "missing the multi by x legs" (where "x" can be any number, but it was usually between 1 and 3).

Thanks for your help.

20's | Total | Probability |
---|---|---|

4 | 96,154,845,853,132,800 | 0.000115 |

3 | 3,423,358,427,452,540,000 | 0.004084 |

2 | 44,788,356,273,817,700,000 | 0.053435 |

1 | 255,238,297,847,250,000,000 | 0.304514 |

0 | 534,635,239,424,785,000,000 | 0.637851 |

Total | 838,181,406,819,158,000,000 | 1.000000 |

Totals:

0 x 20 = ?

1 x 20 = 60***

2 x 20 = 11

3 x 20 = 0

4 x 20 = 0

***: Below is the break-downs for the "sidebet spinner"

Odds (to 1) / No. of times it occurred

Push / 20

1 / 23

2 / 13

3 / 4 (no change from last test)

Note 1: To make it easier, I am now writing the "No. of times it occurred" in numerals (previously it was written in words).

Note 2: Sample size still probably too small.

Note 3: Anyone can add my figures to their testing, if they like.

3x: 0

2x: 4

1x: 16

Push: 10

Adding my results to those of ksdjdj, I get the following totals:

Multiplier | Wiz 12-24-21 | ksdjdj | Total |
---|---|---|---|

0 | 10 | 20 | 30 |

1 | 16 | 23 | 39 |

2 | 4 | 13 | 17 |

3 | 0 | 4 | 4 |

Total | 30 | 60 | 90 |

This leads to an average spin result of 1.944444444. Remember, if it lands on a line, it is a push and all other wins are on a "to one" basis.

Putting this average multiplier into the overall return, I get the following table. The lower right cell shows a return of 93.57%.

Twenties | Pays | Probability | Return |
---|---|---|---|

4 | 420 | 0.000115 | 0.048182 |

3 | 20 | 0.004084 | 0.081685 |

2 | 4 | 0.053435 | 0.213741 |

1 | 1.94 | 0.304514 | 0.592111 |

0 | 0 | 0.637851 | 0.000000 |

Total | 1.000000 | 0.935719 |

To play for free, try this link.

0 (Push) / 32

1x / 43

2x / 20

3x / 5

Quote:Wizard(snip)

Putting this average multiplier into the overall return, I get the following table. The lower right cell shows a return of 93.57%.

Twenties Pays Probability Return 4 420 0.000115 0.048182 3 20 0.004084 0.081685 2 4 0.053435 0.213741 1 1.94 0.304514 0.592111 0 0 0.637851 0.000000 Total 1.000000 0.935719

(snip)

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In the above table, are all the figures under the heading "Pays" correct ?

I think you need to change it from:

"420", "20" and "4" to "421", "21" and "5" ?

Quote:ksdjdjI just did 10 more spins, so now the combined total is 100 (results below inc. Wiz's results from his previous post):

0 (Push) / 32

1x / 43

2x / 20

3x / 5

First, you're right, I should have adjusted everything to a "for one" basis. When I do that, based on the 90 spins of data, I get the following return.

Twenties | Pays | Probability | Return |
---|---|---|---|

4 | 421 | 0.000000 | 0.048296 |

3 | 21 | 0.066667 | 0.085770 |

2 | 5 | 0.283333 | 0.267176 |

1 | 1.94 | 0.650000 | 0.592111 |

0 | 0 | 1.000000 | 0.000000 |

Total | 0.000000 | 0.993353 |

Here is my updated table of spins. I would prefer if you gather more data, let me know just the new data.

Multiplier | Wiz | ksdjdj | Total |
---|---|---|---|

0 | 10 | 22 | 32 |

1 | 16 | 27 | 43 |

2 | 4 | 16 | 20 |

3 | 0 | 5 | 5 |

Total | 30 | 70 | 100 |

With your windfall of 2x multipliers, here is my new return table for the side bet.

Twenties | Pays | Probability | Return |
---|---|---|---|

4 | 421 | 0.000000 | 0.048296 |

3 | 21 | 0.073529 | 0.085770 |

2 | 5 | 0.294118 | 0.267176 |

1 | 1.98 | 0.632353 | 0.602938 |

0 | 0 | 1.000000 | 0.000000 |

Total | 0.000000 | 1.004180 |

Quote:Wizard(snip)I would prefer if you gather more data, let me know just the new data.

(snip)

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Just did another 10 spins, here are the results:

Push / 2

1 / 7

2 / 0

3 / 1

Quote:WizardThe game help file claims a return of 99.58%, which I presume to be a weighted blend of the base game and side bet. My house edge calculator gives a house edge of the game game of 0.5744%. That means the side bet would have a player advantage of 0.1976%.

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It is also double after split, so the house edge is 0.43286% for each of the 4 boxes in the main game ?

Quote:ksdjdjIt is also double after split, so the house edge is 0.43286% for each of the 4 boxes in the main game ?

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You're right, I see it is double after a split. I did a few more spins. Here is my new table showing our combined data.

Multiplier | Wiz | ksdjdj | Total | Probability | Expected |
---|---|---|---|---|---|

0 | 11 | 24 | 35 | 0.307018 | 0.307018 |

1 | 17 | 34 | 51 | 0.447368 | 0.894737 |

2 | 6 | 16 | 22 | 0.192982 | 0.578947 |

3 | 0 | 6 | 6 | 0.052632 | 0.210526 |

Total | 34 | 80 | 114 | 1.000000 | 1.991228 |

I suspect our results are exceeding expectations.

Limited testing, but the sidebet did appear to be resolved before insurance was offered.

Quote:gordonm888So we calculate that the basic BJ game should have an expectation of 99.57% which is very close to the value of 99.58% posted on the game's Help/Info page? Is this making sense?

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Sort of, I am used to side bets with a separate RTP figure, but if the 99.58% RTP "combined figure ^^^ " is correct then the side bet should also be about 99.58%.

^^^: Since it is a "forced side bet", it is probably safe to say that it is a blended figure?

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Anyone can answer this, but how many tests of the "side bet spinner " do you think would be enough, to get a good feel for it?

There may be at least two answers for the above question:

(i) One answer would be for, when you have "no idea" what the spinner should pay

(ii) The other answer would be for, when you think the average odds could be ~$1.95 (~0.95/1) for the spinner.

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Update (320 am, Pac Time):

Just did another 16 spins, here are the results:

Push / 4

1 / 10

2 / 2

3 / 0

Quote:WizardI would like to announce my new page on Four 20's Blackjack. As always, I welcome all comments, questions, and corrections.

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Looks good to me.

Also, my early estimated chances for the "One 20 Wheel" were:

3 - 5%

2 - 20%

1 - 40%

Push - 35%

I don't like that they disallow surrender but everything else is spot on for good blackjack. (In PA, surrender is if DraftKings offers this game on their PA platform, wouldn't they be required to modify it to allow that option?)

I am assuming electronic blackjack falls under a different set of rules. Hopefully someone more familiar with PA rules can educate me.

Quote:ksdjdjQuote:Wizard

Also, my early estimated chances for the "One 20 Wheel" were:

3 - 5%

2 - 20%

1 - 40%

Push - 35%

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Here's data on an additional 20 spins on the One 20 Wheel:

3: 2

2: 2

1: 10

Push: 6So many better men, a few of them friends, are dead. And a thousand thousand slimy things live on, and so do I.

3x: 5%

2x: 15%

1x: 50%

Push: 30%