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Irregular table read by rows: n-sect the angles of a heptagon. Then T(n,k) = number of k-sided polygons in that figure for k >= 3.
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%I #13 Jul 20 2020 18:57:37

%S 0,0,0,0,1,14,21,56,0,0,0,0,0,0,0,0,0,1,84,28,35,7,7,0,1,182,56,14,

%T 189,196,70,21,0,7,0,0,0,0,0,1,280,210,42,378,252,140,63,7,7,0,0,0,0,

%U 0,1,238,196,14,448,588,126,63,21,14,0,0,0,0,0,1

%N Irregular table read by rows: n-sect the angles of a heptagon. Then T(n,k) = number of k-sided polygons in that figure for k >= 3.

%C For n<=200 no polygon has more than 14 edges.

%C See A335757 for illustrations.

%H Lars Blomberg, <a href="/A335760/b335760.txt">Table of n, a(n) for n = 1..1777</a> (the first 200 rows)

%e The table begins

%e 0, 0, 0, 0, 1;

%e 14;

%e 21, 56, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1;

%e 84, 28;

%e 35, 7, 7, 0, 1;

%e 182, 56, 14;

%e 189, 196, 70, 21, 0, 7, 0, 0, 0, 0, 0, 1;

%e 280, 210, 42;

%e 378, 252, 140, 63, 7, 7, 0, 0, 0, 0, 0, 1;

%e 238, 196, 14;

%e 448, 588, 126, 63, 21, 14, 0, 0, 0, 0, 0, 1;

%Y Cf. A329714 (n-sected sides, not angles), A335757 (regions), A335758 (vertices), A335759 (edges).

%K nonn,tabf

%O 1,6

%A _Lars Blomberg_, Jun 22 2020