The following pictures show n unit equilateral triangles packed inside the smallest known domino (of shortest side length s).
1-2. 
s = √3/2
Trivial.
3. 
s = .96796+
Found by Jonathan Viquerat
in April 2026.
4. 
s = 1.12036+
Found by Jonathan Viquerat
in April 2026.
5. 
s = 1.26315+
Found by Jonathan Viquerat
in April 2026.
6. 
s = 1.37629+
Found by Jonathan Viquerat
in April 2026.
7. 
s = 1.49076+
Found by Jonathan Viquerat
in April 2026.
8. 
s = 1.56293+
Found by Jonathan Viquerat
in April 2026.
9. 
s = 1.64882+
Found by Bhavithran Ananthan
in July 2026.
10. 
s = 1.68302+
Found by Aapo Lipponen
in July 2026.
11. 
s = 1.72969+
Found by Joshua Wolk
in September 2026.
12. 
s = 1.74022+
Found by Jonathan Viquerat
in September 2026.
13. 
s = 1.85319+
Found by Jonathan Viquerat
in April 2026.
14. 
s = 3(3–√3)/2 = 1.90192+
Found by Jonathan Viquerat
in April 2026.
15. 
s = 1.97875+
Found by Joshua Wolk
in September 2026.
16. 
s = 2
Found by Jonathan Viquerat
in April 2026.
17. 
s = 2.10306+
Found by Jonathan Viquerat
in April 2026.
18. 
s = 2.14913+
Found by Jonathan Viquerat
in April 2026.
19. 
s = 2.24321+
Found by Thomas Schadt
in September 2026.
20. 
s = 2.29729+
Found by Aapo Lipponen
in July 2026.
21. 
s = 2.36065+
Found by Thomas Schadt
in September 2026.
22. 
s = 2.40089+
Found by Joshua Wolk
in September 2026.
23. 
s = 2.45223+
Found by Joshua Wolk
in September 2026.
24. 
s = 2.47803+
Found by Joshua Wolk
in September 2026.
25. 
s = 2.51458+
Found by Joshua Wolk
in September 2026.
26. 
s = 2.54759+
Found by Thomas Schadt
in September 2026.
28. 
s = 2.56837+
Found by Thomas Schadt
in September 2026.
28. 
s = 2.59434+
Found by Thomas Schadt
in September 2026.
29. 
s = 2.64841+
Found by Thomas Schadt
in September 2026.
30. 
s = 2.69222+
Found by Thomas Schadt
in September 2026.
31. 
s = 2.72708+
Found by Thomas Schadt
in September 2026.
32. 
s = 2.77024+
Found by Thomas Schadt
in September 2026.
33. 
s = 2.84139+
Found by Thomas Schadt
in September 2026.
34. 
s = 2.87515+
Found by Thomas Schadt
in September 2026.
35. 
s = 2.91827+
Found by Thomas Schadt
in September 2026.
36. 
s = 2.96585+
Found by Thomas Schadt
in September 2026.
37. 
s = 3.00891+
Found by Thomas Schadt
in September 2026.
38. 
s = 3.05515+
Found by Thomas Schadt
in September 2026.
39. 
s = 3.10039+
Found by Thomas Schadt
in September 2026.
40. 
s = 3.13895+
Found by Thomas Schadt
in September 2026.
41. 
s = 3.17722+
Found by Thomas Schadt
in September 2026.
42. 
s = 3.21847+
Found by Thomas Schadt
in September 2026.
43. 
s = 3.25011+
Found by Thomas Schadt
in September 2026.
44. 
s = 3.28461+
Found by Thomas Schadt
in September 2026.
45. 
s = 3.31131+
Found by Thomas Schadt
in September 2026.
46. 
s = 3.33134+
Found by Thomas Schadt
in September 2026.
47. 
s = 3.36472+
Found by Thomas Schadt
in September 2026.
48. 
s = 3.38757+
Found by Thomas Schadt
in September 2026.
49. 
s = 3.41214+
Found by Thomas Schadt
in September 2026.
50. 
s = 3.43805+
Found by Thomas Schadt
in September 2026.