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A331931 The number of regions inside a hexagon formed by the straight line segments mutually connecting all vertices and all points that divide the sides into n equal parts.

%I A331931 #26 May 12 2020 04:43:41
%S A331931 24,408,2268,8208,20832,44640,89214,154752,249906,390012,590658,
%T A331931 824712,1183704,1580868,2067162,2770476,3585582,4397172,5665818,
%U A331931 6827736,8318976,10209948,12364098,14395164,17194230,20216808,23436612,27124416,31817676,35516328
%N A331931 The number of regions inside a hexagon formed by the straight line segments mutually connecting all vertices and all points that divide the sides into n equal parts.
%C A331931 The terms are from numeric computation - no formula for a(n) is currently known.
%H A331931 Scott R. Shannon, <a href="/A331931/a331931.png">Hexagon regions for n = 1</a>.
%H A331931 Scott R. Shannon, <a href="/A331931/a331931_1.png">Hexagon regions for n = 2</a>.
%H A331931 Scott R. Shannon, <a href="/A331931/a331931_2.png">Hexagon regions for n = 3</a>.
%H A331931 Scott R. Shannon, <a href="/A331931/a331931_6.png">Hexagon regions for n = 4</a>.
%H A331931 Scott R. Shannon, <a href="/A331931/a331931_4.png">Hexagon regions for n = 5</a>.
%H A331931 Scott R. Shannon, <a href="/A331931/a331931_5.png">Hexagon regions for n = 6</a>.
%H A331931 Scott R. Shannon, <a href="/A331931/a331931_7.png">Hexagon regions for n = 7</a>.
%H A331931 Scott R. Shannon, <a href="/A331931/a331931_8.png">Hexagon regions for n = 8</a>.
%H A331931 Scott R. Shannon, <a href="/A331931/a331931_9.png">Hexagon regions for n = 5, with random distance-based coloring</a>.
%H A331931 Scott R. Shannon, <a href="/A331931/a331931_10.png">Hexagon regions for n = 6, with random distance-based coloring</a>.
%H A331931 Wikipedia, <a href="https://en.wikipedia.org/wiki/Hexagon">Hexagon</a>.
%Y A331931 Cf. A331932 (n-gons), A330845 (edges), A330846 (vertices), A007678, A092867, A331452, A331929.
%K A331931 nonn
%O A331931 1,1
%A A331931 _Scott R. Shannon_ and _N. J. A. Sloane_, Feb 01 2020
%E A331931 a(9)-a(30) from _Lars Blomberg_, May 12 2020