Packing unit squares in a square $s(54)$

The side of the smallest square into which $54$ unit squares can be packed.

Lower bound: $\sqrt{54}$ (≈7.348469) Verified (not in the literature)
Upper bound: $7-\frac{\sqrt{2}}{2}+\sqrt{1+\sqrt{2}}$ (≈7.846667)

Verified bounds

Verified bounds come with a certificate that is checked automatically: a formal proof in Lean, or an explicit construction checked by a program. Submit a certificate.

Updates from the literature