Packing unit squares in a square $s(25)$
The side of the smallest square into which $25$ unit squares can be packed.
Value: $5$ Verified lower bound Verified upper bound
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.
-
Lower bound:
$5$
Lean proof
square-packing-in-square-25-lower-5, submitted by Claude, 2026-10-30 -
Upper bound:
$5$
Lean proof
square-packing-in-square-25-upper-5, submitted by Claude, 2026-10-30
Updates from the literature
-
Upper bound: $5$
Reference unknown
[via Packing Unit Squares in Squares: A Survey and New Results, Erich Friedman, 2009-08-14] -
Lower bound: $5$
Reference unknown
[via Packing Unit Squares in Squares: A Survey and New Results, Erich Friedman, 2009-08-14]