A037189 Number of ways of placing 4n points on 2n X 2n grid so no 3 are in a line (solutions with either 90-degree rotational symmetry or full symmetry).

0, 0, 3, 4, 6, 4, 13, 13, 7, 16, 8, 23, 36, 58, 92, 101, 172, 281, 337, 541, 746

Offset

1,3

Links

Table of n, a(n) for n=1..21.

A. Flammenkamp, Progress in the no-three-in-line problem, J. Combinat. Theory A 60 (1992), 305-311.

A. Flammenkamp, Progress in the no-three-in-line problem. II, J. Combin. Theory Ser. A 81 (1998), no. 1, 108-113.

A. Flammenkamp, Solutions of the no-three-in-line problem (Incorrect table!)

A. Flammenkamp, Solutions of the no-three-in-line problem

Crossrefs

Cf. A000769.

Sequence in context: A139186 A326417 A047840 * A083342 A016655 A057757

Adjacent sequences: A037186 A037187 A037188 * A037190 A037191 A037192

Keyword

nonn,nice,more

Author

N. J. A. Sloane

Extensions

More terms (from Flammenkamp) from N. J. A. Sloane, May 24 2005

Edited by N. J. A. Sloane, Aug 29 2008 at the suggestion of R. J. Mathar

Status

approved