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%I #28 May 16 2020 06:32:12
%S 154,2754,16858,55098,142318,298350,568162,975294,1585666,2426292,
%T 3588508,5093604,7067422,9523746,12612214,16351218,20924029,26326026,
%U 32789107,40289238,49093282,59181228,70852528
%N 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.
%C The terms are from numeric computation - no formula for a(n) is currently known.
%H Scott R. Shannon, <a href="/A332421/a332421.png">Nonagon regions for n = 1</a>.
%H Scott R. Shannon, <a href="/A332421/a332421_1.png">Nonagon regions for n = 2</a>.
%H Scott R. Shannon, <a href="/A332421/a332421_2.png">Nonagon regions for n = 3</a>.
%H Scott R. Shannon, <a href="/A332421/a332421_3.png">Nonagon regions with random distance-based coloring for n = 1</a>.
%H Scott R. Shannon, <a href="/A332421/a332421_4.png">Nonagon regions with random distance-based coloring for n = 2</a>.
%H Scott R. Shannon, <a href="/A332421/a332421_5.png">Nonagon regions with random distance-based coloring for n = 3</a>.
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Nonagon">Nonagon</a>.
%Y Cf. A332427 (n-gons), A332428 (vertices), A332429 (edges), A007678, A092867, A331452, A331929.
%K nonn,more
%O 1,1
%A _Scott R. Shannon_ and _N. J. A. Sloane_, Mar 09 2020
%E a(6)-a(23) from _Lars Blomberg_, May 16 2020
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