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  • Only two legal plays

    From Timothy Chow@21:1/5 to All on Sat Sep 17 08:47:30 2022
    XGID=-HEA--a-----------Abbcbda-:1:1:1:32:0:0:0:0:10

    X:Player 1 O:Player 2
    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X | | O O O O O O |
    | | | O O O O O |
    | | | O O |
    | | | O |
    | | | |
    | |BAR| |
    | | | X 8 |
    | | | X X |
    | | | X X | +---+
    | | | X X | | 2 |
    | | | O X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 39 O: 68 X-O: 0-0
    Cube: 2, X own cube
    X to play 32

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Sat Sep 17 10:36:05 2022
    On 9/17/2022 8:47 AM, Timothy Chow wrote:
    XGID=-HEA--a-----------Abbcbda-:1:1:1:32:0:0:0:0:10

    X:Player 1   O:Player 2
    Score is X:0 O:0. Unlimited Game
     +13-14-15-16-17-18------19-20-21-22-23-24-+
     |                X |   | O  O  O  O  O  O |
     |                  |   | O  O  O  O  O    |
     |                  |   |       O     O    |
     |                  |   |             O    |
     |                  |   |                  |
     |                  |BAR|                  |
     |                  |   |             X  8 |
     |                  |   |             X  X |
     |                  |   |             X  X | +---+
     |                  |   |             X  X | | 2 |
     |                  |   | O        X  X  X | +---+
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 39  O: 68 X-O: 0-0
    Cube: 2, X own cube
    X to play 32

    18/13 gives X more rolls to slip past the remaining opponent's checker,
    but also exposes more immediate hits, but 6 shots vs 5 shots seems like
    not that much.

    By playing 3/2 X avoids having a second checker sent back, and while
    that's not much either, two not muches seems to add up to something.
    18/15 3/2.

    --
    Ah....Clem
    The future is fun, the future is fair.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Tue Sep 20 08:26:00 2022
    XGID=-HEA--a-----------Abbcbda-:1:1:1:32:0:0:0:0:10

    X:Player 1 O:Player 2
    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X | | O O O O O O |
    | | | O O O O O |
    | | | O O |
    | | | O |
    | | | |
    | |BAR| |
    | | | X 8 |
    | | | X X |
    | | | X X | +---+
    | | | X X | | 2 |
    | | | O X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 39 O: 68 X-O: 0-0
    Cube: 2, X own cube
    X to play 32

    There are similarities between this position and Paul's recent
    "sandwich" problem. Improving X's chances of getting past O's
    straggler is huge.

    1. Rollout¹ 18/13 eq:+0.541
    Player: 62.71% (G:0.04% B:0.00%)
    Opponent: 37.29% (G:1.22% B:0.02%)
    Confidence: ±0.006 (+0.535..+0.547) - [100.0%]

    2. Rollout¹ 18/15 3/1 eq:+0.358 (-0.183)
    Player: 59.02% (G:0.04% B:0.00%)
    Opponent: 40.98% (G:0.62% B:0.01%)
    Confidence: ±0.006 (+0.352..+0.364) - [0.0%]

    ¹ 1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller

    eXtreme Gammon Version: 2.19.207.pre-release

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pepstein5@gmail.com@21:1/5 to Tim Chow on Tue Sep 27 15:15:40 2022
    On Tuesday, September 20, 2022 at 1:26:01 PM UTC+1, Tim Chow wrote:
    XGID=-HEA--a-----------Abbcbda-:1:1:1:32:0:0:0:0:10

    X:Player 1 O:Player 2
    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X | | O O O O O O |
    | | | O O O O O |
    | | | O O |
    | | | O |
    | | | |
    | |BAR| |
    | | | X 8 |
    | | | X X |
    | | | X X | +---+
    | | | X X | | 2 |
    | | | O X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 39 O: 68 X-O: 0-0
    Cube: 2, X own cube
    X to play 32
    There are similarities between this position and Paul's recent
    "sandwich" problem. Improving X's chances of getting past O's
    straggler is huge.
    Sorry, I don't remember any sandwich problem.
    Are you sure you don't mean "problem sandwich"?
    I have sometimes experienced sandwiches that are so thick that I
    can barely get them into my mouth, and these would be problem sandwiches.

    Paul

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to peps...@gmail.com on Tue Sep 27 23:27:32 2022
    On 9/27/2022 6:15 PM, peps...@gmail.com wrote:
    On Tuesday, September 20, 2022 at 1:26:01 PM UTC+1, Tim Chow wrote:
    XGID=-HEA--a-----------Abbcbda-:1:1:1:32:0:0:0:0:10

    X:Player 1 O:Player 2
    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X | | O O O O O O |
    | | | O O O O O |
    | | | O O |
    | | | O |
    | | | |
    | |BAR| |
    | | | X 8 |
    | | | X X |
    | | | X X | +---+
    | | | X X | | 2 |
    | | | O X X X | +---+
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 39 O: 68 X-O: 0-0
    Cube: 2, X own cube
    X to play 32
    There are similarities between this position and Paul's recent
    "sandwich" problem. Improving X's chances of getting past O's
    straggler is huge.
    Sorry, I don't remember any sandwich problem.

    Anyone who solves this problem correctly will get a sandwich!

    https://groups.google.com/g/rec.games.backgammon/c/CtFrvXIDCfU/m/vNNV2BnPDAAJ

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Fri Jun 30 08:46:57 2023
    XGID=--BBbCBCB-----b--bbcac---A:1:-1:1:65:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O O | | O O O | +---+
    | O O O | | O O | | 2 |
    | | | O O | +---+
    | | | |
    | | X | |
    | |BAR| |
    | | | |
    | | | |
    | X | | X |
    | X X | | X X O X X |
    | X X | | X X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 99 O: 129 X-O: 0-0
    Cube: 2, O own cube
    X to play 65

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From ah....Clem@21:1/5 to Timothy Chow on Sat Jul 1 12:54:04 2023
    On 6/30/2023 8:46 AM, Timothy Chow wrote:
    XGID=--BBbCBCB-----b--bbcac---A:1:-1:1:65:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
     +13-14-15-16-17-18------19-20-21-22-23-24-+
     |    O        O  O |   | O  O  O          | +---+
     |    O        O  O |   | O     O          | | 2 |
     |                  |   | O     O          | +---+
     |                  |   |                  |
     |                  | X |                  |
     |                  |BAR|                  |
     |                  |   |                  |
     |                  |   |                  |
     |                X |   |    X             |
     |             X  X |   | X  X  O  X  X    |
     |             X  X |   | X  X  O  X  X    |
     +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count  X: 99  O: 129 X-O: 0-0
    Cube: 2, O own cube
    X to play 65

    I'll keep the prime and slot the ace. It leaves more shots, but O's
    board is weak and if she enters on the ace, hitting in the process
    doesn't gain that much since she's still on the ace. Meanwhile, four
    primes can be surprisingly powerful.

    bar/20* 7/1.

    --
    Ah....Clem
    The future is fun, the future is fair.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Sun Jul 2 09:58:46 2023
    XGID=--BBbCBCB-----b--bbcac---A:1:-1:1:65:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | O O O | | O O O | +---+
    | O O O | | O O | | 2 |
    | | | O O | +---+
    | | | |
    | | X | |
    | |BAR| |
    | | | |
    | | | |
    | X | | X |
    | X X | | X X O X X |
    | X X | | X X O X X |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 99 O: 129 X-O: 0-0
    Cube: 2, O own cube
    X to play 65

    I thought along similar lines as ah...clem, and played 7/1. But X
    is far ahead in the pip count, and just needs to bring his straggler
    home. His primary game plan is to race, or possibly to attack, but
    certainly not to prime. So breaking his prime is not very costly,
    but getting hit would be.

    1. Rollout¹ Bar/20* 8/2 eq:+0.423
    Player: 67.37% (G:26.06% B:0.40%)
    Opponent: 32.63% (G:4.63% B:0.17%)
    Confidence: ±0.009 (+0.415..+0.432) - [100.0%]

    2. Rollout¹ Bar/20* 7/1 eq:+0.335 (-0.088)
    Player: 64.95% (G:25.34% B:0.40%)
    Opponent: 35.05% (G:6.24% B:0.24%)
    Confidence: ±0.009 (+0.326..+0.344) - [0.0%]

    ¹ 1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller

    eXtreme Gammon Version: 2.19.211.pre-release

    ---
    Tim Chow

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