A332421 The number of regions inside a nonagon formed by the straight line segments mutually connecting all vertices and all points that divide the sides into n equal parts.

154, 2754, 16858, 55098, 142318, 298350, 568162, 975294, 1585666, 2426292, 3588508, 5093604, 7067422, 9523746, 12612214, 16351218, 20924029, 26326026, 32789107, 40289238, 49093282, 59181228, 70852528

Offset

1,1

Comments

The terms are from numeric computation - no formula for a(n) is currently known.

Links

Table of n, a(n) for n=1..23.

Scott R. Shannon, Nonagon regions for n = 1.

Scott R. Shannon, Nonagon regions for n = 2.

Scott R. Shannon, Nonagon regions for n = 3.

Scott R. Shannon, Nonagon regions with random distance-based coloring for n = 1.

Scott R. Shannon, Nonagon regions with random distance-based coloring for n = 2.

Scott R. Shannon, Nonagon regions with random distance-based coloring for n = 3.

Wikipedia, Nonagon.

Crossrefs

Cf. A332427 (n-gons), A332428 (vertices), A332429 (edges), A007678, A092867, A331452, A331929.

Sequence in context: A160841 A160853 A235099 * A227977 A282557 A200709

Adjacent sequences: A332418 A332419 A332420 * A332422 A332423 A332424

Keyword

nonn,more

Author

Scott R. Shannon and N. J. A. Sloane, Mar 09 2020

Extensions

a(6)-a(23) from Lars Blomberg, May 16 2020

Status

approved