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%I #10 Jun 12 2020 08:41:55
%S 1,6,12,3,3,1,24,6,36,9,9,7,48,24,6,72,21,15,19,84,48,12,6,108,51,33,
%T 25,126,90,12,6,168,69,51,43,180,120,48,18,216,123,81,49,240,180,54,
%U 36,288,171,99,73,312,234,84,48,372,225,117,103,396,288,126,60
%N Irregular table read by rows: T(n,k) = number of k-sided polygons formed by n-secting the angles of an equilateral triangle for k >= 3.
%C See A277402 for illustrations.
%H Lars Blomberg, <a href="/A335413/b335413.txt">Table of n, a(n) for n = 1..1991</a>
%e Table begins:
%e 1;
%e 6;
%e 12, 3, 3, 1;
%e 24, 6;
%e 36, 9, 9, 7;
%e 48, 24, 6;
%e 72, 21, 15, 19;
%e 84, 48, 12, 6;
%e 108, 51, 33, 25;
%e 126, 90, 12, 6;
%e 168, 69, 51, 43;
%e 180, 120, 48, 18;
%e 216, 123, 81, 49;
%e 240, 180, 54, 36;
%e 288, 171, 99, 73;
%e 312, 234, 84, 48;
%Y Cf. A277402 (regions), A335411 (vertices), A335412 (edges).
%K nonn,tabf
%O 1,2
%A _Lars Blomberg_, Jun 08 2020