MinMax Arena
中/EN
P89 · Packing and covering · Classic · Hard

Tans in a square · n = 24

Pack n tans (right isosceles triangles of leg 1) into a square. Contact is allowed; interiors cannot overlap. Minimise the container square side.

Instancen = 24
ObjectiveMinimize container square side
Best known, unproven3.517Source-precision interval: 3.517–3.518 (values inside match)exhibited site certificate 3.517000007Compiled by Erich Friedman; Found by David W. Cantrell in August 2007. Source expression: s = 3.517+.

Formal definition

  • ContainerThe editor and certificate normalize to the unit square [0,1]². This is a coordinate convention only; scores use the literature's unit-piece scale. Boundary contact is allowed.
  • SubmissionSubmit {radius, placements:[{x,y,turn,quarter},…]}, with x, y and turn as decimal strings of at most nine places. radius is the piece's short side (the leg, the domino's short side, the cell side); the container side is 1/radius. x,y is the centre of the piece's bounding box; quarter is an integer 0–3, an exact number of right angles applied about the centre before the rational turn = tan(θ/2). Coordinates and turn lie in ±4; 0 < radius ≤ 4.
  • ConstraintsExactly n congruent shapes lie wholly in the container with pairwise disjoint interiors. Polygon rotations are independent, not limited to quarter turns.
  • PrecisionInput decimals are exact rationals; regular-polygon vertices are algebraic, not rounded templates. Feasibility has no floating-point tolerance. A finite-decimal certificate is not a continuous optimality proof.
  • Objectivecontainer square side = 1/r (r is the piece's short side inside the unit square), smaller is better. Pages, leaderboards and literature records share this unit; nothing is converted by hand.
Open the full editor ↗
VERIFIED CONSTRUCTIONVERIFIED CONSTRUCTION

Getting a feel for it

Source and certificate

External targets are converted with their printed precision; decimal coordinate certificates are separate. Reconstruction loss never lowers the literature target, and a source construction is not automatically an optimality proof.

Source
The record-holding arrangement for Tans in a square n = 24, 3.517000007
Current leader

3.517000007

container square side

Matches the best known
Answer sourceDavid W. Cantrell
Solution methodPublished reference construction
Challenge this record ↗Submit a proof / idea ↓Share a proof or idea in the discussion. Accepted contributions can earn proof points.
Record holder's solver noteNo solver note yet (expand)＋

The record holder has not shared a solver note yet.

ANSWER FORMAT

How to write your answer

the unit square [0,1]²

Submit {radius, placements:[{x,y,turn,quarter},…]}, with x, y and turn as decimal strings of at most nine places. radius is the piece's short side (the leg, the domino's short side, the cell side); the container side is 1/radius. x,y is the centre of the piece's bounding box; quarter is an integer 0–3, an exact number of right angles applied about the centre before the rational turn = tan(θ/2). Coordinates and turn lie in ±4; 0 < radius ≤ 4.

The current leader's answer

{
  "placements": [
    {
      "quarter": 3,
      "turn": "-0.414213562",
      "x": "0.798848742",
      "y": "0.402302521"
    },
    {
      "quarter": 1,
      "turn": "0.396521633",
      "x": "0.396192022",
      "y": "0.798941620"
    },
    {
      "turn": "-0.414213562",
      "x": "0.597697479",
      "y": "0.201151258"
    },
    {
      "turn": "-0.003498798",
      "x": "0.143227333",
      "y": "0.429707091"
    },
    {
      "quarter": 1,
      "turn": "0.400636497",
      "x": "0.201034191",
      "y": "0.576934430"
    },
    {
      "quarter": 2,
      "turn": "0.000000000",
      "x": "0.573293292",
      "y": "0.857764401"
    },
    {
      "quarter": 2,
      "turn": "0.000000000",
      "x": "0.857764470",
      "y": "0.857764467"
    },
    {
      "turn": "0.000000000",
      "x": "0.857764128",
      "y": "0.857764532"
    },
    {
      "quarter": 2,
      "turn": "0.000000000",
      "x": "0.857764478",
      "y": "0.573293419"
    },
    {
      "quarter": 2,
      "turn": "-0.003497337",
      "x": "0.141238854",
      "y": "0.145242788"
    },
    {
      "turn": "-0.003495982",
      "x": "0.143226436",
      "y": "0.143226436"
    },
    {
      "turn": "0.000000000",
      "x": "0.426699303",
      "y": "0.142235420"
    },
    {
      "quarter": 1,
      "turn": "-0.414213562",
      "x": "0.201151397",
      "y": "0.999999997"
    },
    {
      "quarter": 2,
      "turn": "-0.414213562",
      "x": "0.000000003",
      "y": "0.798848742"
    },
    {
      "quarter": 3,
      "turn": "-0.414213562",
      "x": "0.617739237",
      "y": "0.612167197"
    },
    {
      "quarter": 1,
      "turn": "-0.414213562",
      "x": "0.606410899",
      "y": "0.612167194"
    },
    {
      "quarter": 2,
      "turn": "-0.414213562",
      "x": "0.405259641",
      "y": "0.411015936"
    },
    {
      "quarter": 1,
      "turn": "-0.414213562",
      "x": "0.798848739",
      "y": "0.402302518"
    },
    {
      "quarter": 2,
      "turn": "-0.414213562",
      "x": "0.597697482",
      "y": "0.201151261"
    },
    {
      "turn": "-0.414213562",
      "x": "0.999999997",
      "y": "0.201151260"
    },
    {
      "quarter": 3,
      "turn": "-0.414213562",
      "x": "0.798848739",
      "y": "0.000000003"
    },
    {
      "quarter": 3,
      "turn": "0.400635788",
      "x": "0.201096709",
      "y": "0.579628994"
    },
    {
      "quarter": 3,
      "turn": "0.396521634",
      "x": "0.395808817",
      "y": "0.786335918"
    },
    {
      "quarter": 3,
      "turn": "0.400636416",
      "x": "0.400575575",
      "y": "0.374139926"
    }
  ],
  "radius": "0.284333238"
}
Submission format and technical detailsOpen this when you are ready to prepare a JSON answer＋

Instance parameters

{
  "n": 24,
  "sides": 5
}

The current leader's answer

{
  "placements": [
    {
      "quarter": 3,
      "turn": "-0.414213562",
      "x": "0.798848742",
      "y": "0.402302521"
    },
    {
      "quarter": 1,
      "turn": "0.396521633",
      "x": "0.396192022",
      "y": "0.798941620"
    },
    {
      "turn": "-0.414213562",
      "x": "0.597697479",
      "y": "0.201151258"
    },
    {
      "turn": "-0.003498798",
      "x": "0.143227333",
      "y": "0.429707091"
    },
    {
      "quarter": 1,
      "turn": "0.400636497",
      "x": "0.201034191",
      "y": "0.576934430"
    },
    {
      "quarter": 2,
      "turn": "0.000000000",
      "x": "0.573293292",
      "y": "0.857764401"
    },
    {
      "quarter": 2,
      "turn": "0.000000000",
      "x": "0.857764470",
      "y": "0.857764467"
    },
    {
      "turn": "0.000000000",
      "x": "0.857764128",
      "y": "0.857764532"
    },
    {
      "quarter": 2,
      "turn": "0.000000000",
      "x": "0.857764478",
      "y": "0.573293419"
    },
    {
      "quarter": 2,
      "turn": "-0.003497337",
      "x": "0.141238854",
      "y": "0.145242788"
    },
    {
      "turn": "-0.003495982",
      "x": "0.143226436",
      "y": "0.143226436"
    },
    {
      "turn": "0.000000000",
      "x": "0.426699303",
      "y": "0.142235420"
    },
    {
      "quarter": 1,
      "turn": "-0.414213562",
      "x": "0.201151397",
      "y": "0.999999997"
    },
    {
      "quarter": 2,
      "turn": "-0.414213562",
      "x": "0.000000003",
      "y": "0.798848742"
    },
    {
      "quarter": 3,
      "turn": "-0.414213562",
      "x": "0.617739237",
      "y": "0.612167197"
    },
    {
      "quarter": 1,
      "turn": "-0.414213562",
      "x": "0.606410899",
      "y": "0.612167194"
    },
    {
      "quarter": 2,
      "turn": "-0.414213562",
      "x": "0.405259641",
      "y": "0.411015936"
    },
    {
      "quarter": 1,
      "turn": "-0.414213562",
      "x": "0.798848739",
      "y": "0.402302518"
    },
    {
      "quarter": 2,
      "turn": "-0.414213562",
      "x": "0.597697482",
      "y": "0.201151261"
    },
    {
      "turn": "-0.414213562",
      "x": "0.999999997",
      "y": "0.201151260"
    },
    {
      "quarter": 3,
      "turn": "-0.414213562",
      "x": "0.798848739",
      "y": "0.000000003"
    },
    {
      "quarter": 3,
      "turn": "0.400635788",
      "x": "0.201096709",
      "y": "0.579628994"
    },
    {
      "quarter": 3,
      "turn": "0.396521634",
      "x": "0.395808817",
      "y": "0.786335918"
    },
    {
      "quarter": 3,
      "turn": "0.400636416",
      "x": "0.400575575",
      "y": "0.374139926"
    }
  ],
  "radius": "0.284333238"
}

Submit {radius, placements:[{x,y,turn,quarter},…]}, with x, y and turn as decimal strings of at most nine places. radius is the piece's short side (the leg, the domino's short side, the cell side); the container side is 1/radius. x,y is the centre of the piece's bounding box; quarter is an integer 0–3, an exact number of right angles applied about the centre before the rational turn = tan(θ/2). Coordinates and turn lie in ±4; 0 < radius ≤ 4. · Verifier v1.0.0

DISCUSSION

Discussion

Talk strategy, share methods, ask why you are stuck. Every signed-in user can post. Posts carry your public byline, the same name your records use; the #number after it is the account's signup ordinal, so a name cannot be worn by someone else. New posts appear after an automated review.

No threads yet. Be the first to talk about this problem?