A338002 The number of regions inside a 4-pointed star formed by the straight line segments mutually connecting all vertices and all points that divide the sides into n equal parts.

56, 816, 6064, 18152, 52088, 100608, 208168, 336840, 579136, 846560, 1310960, 1784888

Offset

1,1

Comments

The star consists of a central square surrounded by four equilateral triangles. See the linked images.

Links

Table of n, a(n) for n=1..12.

Scott R. Shannon, Image of the star with edge-count coloring for n=1.

Scott R. Shannon, Image of the star with edge-count coloring for n=2.

Scott R. Shannon, Image of the star with edge-count coloring for n=3.

Scott R. Shannon, Image of the star with edge-count coloring for n=4.

Scott R. Shannon, Image of the star with edge-count coloring for n=5.

Crossrefs

Cf. A338003 (number of vertices), A331906, A331908, A007678, A092867, A331452.

Sequence in context: A278197 A182866 A008389 * A351410 A219937 A008921

Adjacent sequences: A337999 A338000 A338001 * A338003 A338004 A338005

Keyword

nonn,more

Author

Scott R. Shannon and N. J. A. Sloane, Oct 06 2020

Extensions

a(8)-a(12) from Lars Blomberg, Apr 08 2021

Status

approved