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  • Anyone who solves this problem correctly will get a sandwich!

    From [email protected]@21:1/5 to All on Sun Sep 18 00:28:06 2022
    My title is almost certainly correct.
    It seems extremely unlikely that someone will solve this problem and
    then never eat a sandwich during the entire rest of their life.
    I never suggested any causality.
    On the other hand, there are wheat allergies...
    I think the accuracy of my title is acceptable at p = 0.05 or so, which
    is fine by rgb standards.

    I find this an interesting checkerplay problem, which is deeper than I first thought. Not that much equity at stake, but the choice isn't ultra-marginal either.

    Paul

    XGID=--CB-a--------A-------cbc-:1:-1:1:21:0:1:3:0:10
    X:Daniel O:eXtremeGammon

    Score is X:0 O:1. Unlimited Game, Jacoby Beaver
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X | | O O O | +---+
    | | | O O O | | 2 |
    | | | O O | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | | | X X |
    | | | O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 26 O: 36 X-O: 0-1
    Cube: 2, O own cube
    X to play 21

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Axel Reichert@21:1/5 to [email protected] on Sun Sep 18 10:57:31 2022
    "[email protected]" <[email protected]> writes:

    XGID=--CB-a--------A-------cbc-:1:-1:1:21:0:1:3:0:10
    X:Daniel O:eXtremeGammon

    Score is X:0 O:1. Unlimited Game, Jacoby Beaver
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X | | O O O | +---+
    | | | O O O | | 2 |
    | | | O O | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | | | X X |
    | | | O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 26 O: 36 X-O: 0-1
    Cube: 2, O own cube
    X to play 21

    We are ahead in the race, so want to jump over the last opposing checker
    as soon as possible. 14/11 gives a direct shot and thus is way too
    risky. The partial moves 14/12 and 14/13 both give 6 indirect shots, but
    14/12 is closer to safety. With it goes 2/1 which unstacks and fills a
    gap (whereas 3/2 would stack and not fill a gap). 14/13 mandates 3/1,
    which fills a gap, but does not unstack the heavy 2 point. Staying back
    on point 14 is a two-edged sword with respect to getting/leaving
    shots. No gammons are possible and we do not need to hit.

    14/12 2/1

    Axel

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah...Clem@21:1/5 to [email protected] on Mon Sep 19 12:24:28 2022
    On 9/18/2022 3:28 AM, [email protected] wrote:

    Score is X:0 O:1. Unlimited Game, Jacoby Beaver
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X | | O O O | +---+
    | | | O O O | | 2 |
    | | | O O | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | | | X X |
    | | | O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 26 O: 36 X-O: 0-1
    Cube: 2, O own cube
    X to play 21



    X is far enough ahead in the race that avoiding being hit is priority
    one. Staying on the fourteen exposes 5 shots, moving up to the 12 or 13
    exposes 6 shots, and moving to the 11 exposes 17 shots.

    But, the closer we get to our homeboard, the more rolls we have to run
    past her straggler.

    I'll risk the extra shot to have a better chance of breaking contact.
    Then 2/1 seems like the obvius follow on. I probably won't want to hit
    next roll even if I can, so no worries about leaving a blot in the
    homeboard.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From [email protected]@21:1/5 to ah...Clem on Tue Sep 20 03:49:45 2022
    On Monday, September 19, 2022 at 5:24:32 PM UTC+1, ah...Clem wrote:
    On 9/18/2022 3:28 AM, [email protected] wrote:

    Score is X:0 O:1. Unlimited Game, Jacoby Beaver +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X | | O O O | +---+
    | | | O O O | | 2 |
    | | | O O | +---+
    | | | |
    | | | |
    | |BAR| |
    | | | |
    | | | |
    | | | X |
    | | | X X |
    | | | O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 26 O: 36 X-O: 0-1
    Cube: 2, O own cube
    X to play 21


    X is far enough ahead in the race that avoiding being hit is priority
    one. Staying on the fourteen exposes 5 shots, moving up to the 12 or 13 exposes 6 shots, and moving to the 11 exposes 17 shots.

    But, the closer we get to our homeboard, the more rolls we have to run
    past her straggler.

    I'll risk the extra shot to have a better chance of breaking contact.
    Then 2/1 seems like the obvius follow on. I probably won't want to hit
    next roll even if I can, so no worries about leaving a blot in the homeboard.

    I wrongly made my acepoint.
    1. Rollout¹ 3/1 2/1 eq:+0.583
    Player: 81.96% (G:0.00% B:0.00%)
    Opponent: 18.04% (G:0.00% B:0.00%)
    Confidence: ±0.003 (+0.580..+0.585) - [100.0%]
    Duration: 4.1 seconds

    2. XG Roller+ 14/12 2/1 eq:+0.640 (+0.058)
    Player: 84.44% (G:0.00% B:0.00%)
    Opponent: 15.56% (G:0.00% B:0.00%)

    3. 4-ply 14/12 3/2 eq:+0.579 (-0.004)
    Player: 81.70% (G:0.00% B:0.00%)
    Opponent: 18.30% (G:0.00% B:0.00%)

    4. 4-ply 14/13 3/1 eq:+0.576 (-0.007)
    Player: 81.64% (G:0.00% B:0.00%)
    Opponent: 18.36% (G:0.00% B:0.00%)

    5. 3-ply 3/2 3/1 eq:+0.544 (-0.039)
    Player: 80.48% (G:0.00% B:0.00%)
    Opponent: 19.52% (G:0.00% B:0.00%)


    ¹ 1296 Games rolled with Variance Reduction.
    Moves: 3-ply, cube decisions: XG Roller


    eXtreme Gammon Version: 2.10

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)