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))) = .36816+
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 = 1.41512+
Found by Jonathan Viquerat
in June 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 = 1.61442+
Found by Jonathan Viquerat
in June 2026.
Σ s = 1.68397+
Found by Jonathan Viquerat
in June 2026.
Σ s = 1.75447+
Found by Jonathan Viquerat
in June 2026.
16.
17.
18.
Σ s = 1.81239+
Found by Jonathan Viquerat
in June 2026.
Σ s = 1.86480+
Found by Jonathan Viquerat
in June 2026.
Σ s = 1.92401+
Found by Jonathan Viquerat
in June 2026.
19.
20.
Σ s = 1.97526+
Found by Jonathan Viquerat
in June 2026.
Σ s = 2.03147+
Found by Jonathan Viquerat
in June 2026.