Packing unit squares in a square $s(89)$

The side of the smallest square into which $89$ unit squares can be packed.

Lower bound: $\sqrt{89}$ (≈9.433981) Verified (not in the literature)
Upper bound: $5+\frac{7}{\sqrt{2}}$ (≈9.949747)

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