Computational geometry · explicit constructions

Six improved
upper bounds.

New certified constructions for packing congruent unit squares inside a square, at n = 68, 69, 103, 105, 110, and 131.

01

The problem

How small can the containing square be?

s(n) = least side length that can contain n non-overlapping unit squares

A valid construction with side L establishes s(n) ≤ L. It does not, by itself, prove that L is optimal. This release makes construction claims only.

02

The results

Six explicit packings.

Open any figure to inspect or download the complete SVG geometry. Side lengths below are the interval-validated offered sides.

Certified packing of 68 congruent unit squares

n = 68

Interval verified
Our construction
8.803383074716108386903836683375989697670063329
Cited parent
8.80345993651653
Absolute reduction
0.0000768618004216131

Source contributorsSigvart Brendberg · Thomas Schadt · David Ellsworth

Certified packing of 69 congruent unit squares

n = 69

Interval verified
Our construction
8.827205507815920656880680735618736931225314831
Cited parent
8.82721205592900
Absolute reduction
0.000006548113079343119

Source contributorsMaurizio Morandi · David W. Cantrell

Certified packing of 103 congruent unit squares

n = 103

Interval verified
Our construction
10.703790283762427
Cited parent
10.70383477210707
Absolute reduction
0.000044488344643

Source contributorsThomas Schadt · David Ellsworth

Certified packing of 105 congruent unit squares

n = 105

Interval verified
Our construction
10.807847913867976
Cited parent
10.80789399144854
Absolute reduction
0.000046077580564

Source contributorsThomas Schadt · David Ellsworth

Certified packing of 110 congruent unit squares

n = 110

Interval verified
Our construction
10.996797773597706
Cited parent
10.99683777797875
Absolute reduction
0.000040004381052

Source contributorsDavid W. Cantrell · David Ellsworth

Certified packing of 131 congruent unit squares

n = 131

Interval verified
Our construction
11.956543108124773261501115489978287643498579738
Cited parent
11.95654869347733
Absolute reduction
0.0000055853525567384986

Source contributorsKároly Hajba · David Ellsworth