Dominoes in Octagons

The following pictures show n dominoes (with short side 1) packed inside the smallest known octagon (with side s).


1.
           2.
           3.
s = 3–3/√2 = 0.87867+
Trivial.
 
s = √(4–2√2) = 1.08239+
Trivial.
 
s = √(5–√2–√(8√2–9)) = 1.43690+
Found by Maurizio Morandi
in May 2026.


4.
           5.
           6.
s = 1.57337+
Found by Maurizio Morandi
in May 2026.
s = 1.71644+
Found by Jonathan Viquerat
in June 2026.
s = √(6–√2–√(20√2–26)) = 1.75339+
Found by Maurizio Morandi
in May 2026.


7.
           8.
           9.
s = 2.00513+
Found by Joshua Wolk
in September 2026.
s = 5(√2–1) = 2.07106+
Trivial.
 
s = 2.19803+
Found by Jonathan Viquerat
in June 2026.


10.
           11.
           12.
s = 2.32394+
Found by Jonathan Viquerat
in June 2026.
s = 2.44911+
Found by Jonathan Viquerat
in June 2026.
s = 6(√2–1) = 2.48528+
Trivial.
 


13.
           14.
           15.
s = 2.56542+
Found by Joshua Wolk
in September 2026.
s = 2.67691+
Found by Joshua Wolk
in September 2026.
s = 2.78488+
Found by Joshua Wolk
in September 2026.


16.
           17.
           18.
s = 2√(5–√2–√(8√2–9)) = 2.87381+
Found by Maurizio Morandi
in June 2026.
s = 2.92200+
Found by Joshua Wolk
in September 2026.
s = 2.98881+
Found by Joshua Wolk
in September 2026.


19.
           20.
           21.
s = 3.07779+
Found by Joshua Wolk
in September 2026.
s = 3.16171+
Found by Joshua Wolk
in September 2026.
s = 3.27191+
Found by Joshua Wolk
in September 2026.


22.
           23.
           24.
s = 8(√2–1) = 3.31370+
Found by Maurizio Morandi
in July 2026.
s = 3.31788+
Found by Joshua Wolk
in September 2026.
s = 3.38301+
Found by Joshua Wolk
in September 2026.


25.
           26.
           27.
s = 3.47309+
Found by Joshua Wolk
in September 2026.
s = 2√(6–√2–√(20√2–26)) = 3.50679+
Found by Maurizio Morandi
in July 2026.
s = 10–9/√2 = 3.63603+
Found by Maurizio Morandi
in July 2026.


28.
           29
           30.
s = 9(√2–1) = 3.72792+
Found by Maurizio Morandi
in July 2026.
s = 3.74011+
Found by Joshua Wolk
in September 2026.
s = 3.77874+
Found by Joshua Wolk
in September 2026.


31.
s = 3.80663+
Found by Aapo Lipponen
in July 2026.