The following pictures show n regular pentagons packed inside a unit equilateral triangle, so that the total sum of the sides of the pentagons is as large as possible.
1.
2.
3.
Σ s = 6/(3+3√5+√(6(5+√5))) = .36815+
Trivial.
Σ s = .50395+
Found by Jonathan Viquerat
in June 2026.
Σ s = .73031+
Found by Jonathan Viquerat
in June 2026.
4.
5.
6.
Σ s = .82930+
Found by Jonathan Viquerat
in June 2026.
Σ s = .92964+
Found by Jonathan Viquerat
in June 2026.
Σ s = 1.07719+
Found by Jonathan Viquerat
in June 2026.
7.
8.
9.
Σ s = 1.15736+
Found by Jonathan Viquerat
in June 2026.
Σ s = 1.23720+
Found by Jonathan Viquerat
in June 2026.
Σ s = 1.32596+
Found by Jonathan Viquerat
in June 2026.
10.
11.
12.
Σ s = 1.41659+
Found by Pedro Martins
in July 2026.
Σ s = 1.48404+
Found by Jonathan Viquerat
in June 2026.
Σ s = 1.55059+
Found by Jonathan Viquerat
in June 2026.
13.
14.
15.
Σ s = 1.61529+
Found by Pedro Martins
in October 2026.
Σ s = 1.68627+
Found by Pedro Martins
in July 2026.
Σ s = 1.76162+
Found by Pedro Martins
in October 2026.
16.
17.
18.
Σ s = 1.81473+
Found by Pedro Martins
in October 2026.
Σ s = 1.86983+
Found by Joost de Winter
in October 2026.
Σ s = 1.92778+
Found by Pedro Martins
in October 2026.
19.
20.
21.
Σ s = 1.98517+
Found by Pedro Martins
in October 2026.
Σ s = 2.04173+
Found by Pedro Martins
in October 2026.
Σ s = 2.10003+
Found by Pedro Martins
in October 2026.
22.
23.
24.
Σ s = 2.14716+
Found by Pedro Martins
in October 2026.
Σ s = 2.19806+
Found by Pedro Martins
in October 2026.
Σ s = 2.24421+
Found by Pedro Martins
in October 2026.
25.
26.
27.
Σ s = 2.29239+
Found by Pedro Martins
in October 2026.
Σ s = 2.34280+
Found by Pedro Martins
in October 2026.
Σ s = 2.39101+
Found by Pedro Martins
in October 2026.
28.
29.
30.
Σ s = 2.44145+
Found by Pedro Martins
in October 2026.
Σ s = 2.48162+
Found by Pedro Martins
in October 2026.
Σ s = 2.53081+
Found by Pedro Martins
in October 2026.
31.
32.
33.
Σ s = 2.56926+
Found by Pedro Martins
in October 2026.
Σ s = 2.61222+
Found by Pedro Martins
in October 2026.
Σ s = 2.65162+
Found by Pedro Martins
in October 2026.
34.
35.
36.
Σ s = 2.69513+
Found by Pedro Martins
in October 2026.
Σ s = 2.73724+
Found by Pedro Martins
in October 2026.
Σ s = 2.78128+
Found by Pedro Martins
in October 2026.
37.
38.
39.
Σ s = 2.81652+
Found by Pedro Martins
in October 2026.
Σ s = 2.85502+
Found by Pedro Martins
in October 2026.
Σ s = 2.89096+
Found by Pedro Martins
in October 2026.
40.
41.
42.
Σ s = 2.93158+
Found by Pedro Martins
in October 2026.
Σ s = 2.96966+
Found by Pedro Martins
in October 2026.
Σ s = 3.00597+
Found by Pedro Martins
in October 2026.
43.
44.
45.
Σ s = 3.04532+
Found by Pedro Martins
in October 2026.
Σ s = 3.08272+
Found by Pedro Martins
in October 2026.
Σ s = 3.12135+
Found by Pedro Martins
in October 2026.
46.
47.
48.
Σ s = 3.15295+
Found by Pedro Martins
in October 2026.
Σ s = 3.18631+
Found by Pedro Martins
in October 2026.
Σ s = 3.21968+
Found by Pedro Martins
in October 2026.
49.
50.
Σ s = 3.25090+
Found by Pedro Martins
in October 2026.
Σ s = 3.28857+
Found by Pedro Martins
in October 2026.