No-three-in-line $D(37)$
The largest number of points of the $37 \times 37$ grid with no three on a line.
Value: $74$ Verified lower 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:
$74$
Checked construction
no-three-in-line-37-lower-74, submitted by daniel-munro, 2026-11-05
[construction from The No-Three-in-Line Problem, Achim Flammenkamp, 2026-10-28] - Upper bound: None yet
Updates from the literature
-
Upper bound: $74$
Trivial or easy according to the secondary source.
[via No-three-in-line problem - Wikipedia] -
1998-01
Lower bound: $74$
A. Flammenkamp, Progress in the no-three-in-line problem, II, Journal of Combinatorial Theory, Series A 81 (1998) 108-113.
[via The No-Three-in-Line Problem, Achim Flammenkamp, 2026-10-28]