A296468 Largest number of points that can be placed on an n X n point grid so that no point is equally distant from two other points on the same row or column.

1, 4, 6, 11, 17, 24, 28, 32, 40, 47, 57, 66, 78, 90

Offset

1,2

Comments

This sequence is a 2-dimensional generalization of A003002 ("no 3-term arithmetic progressions").

Links

Table of n, a(n) for n=1..14.

Example

Up to 66 points (x) may be placed on a 12 X 12 point grid. Example with two symmetry axes:
x x . x x . . . . x x .
x . x . . x x . . x . x
. x x . . . . x x . x x
x . . . . x x . x x . .
x . . . x . x x . x . .
. x . x . . . x x . x .
. x . x x . . . x . x .
. . x . x x . x . . . x
. . x x . x x . . . . x
x x . x x . . . . x x .
x . x . . x x . . x . x
. x x . . . . x x . x x

Crossrefs

Cf. A003002, A193838, A300131.

Sequence in context: A343341 A343345 A343346 * A060577 A360042 A360361

Adjacent sequences: A296465 A296466 A296467 * A296469 A296470 A296471

Keyword

nonn,hard,more,nice

Author

Heinrich Ludwig, Dec 13 2017

Extensions

a(13)-a(14) from Bert Dobbelaere, Jan 06 2020

Status

approved