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%I #9 Jun 03 2020 05:27:06
%S 4,84,20,692,312,72,4,2708,2020,400,88,0,4,7876,5764,1580,264,20,4,
%T 18220,14868,4960,904,112,24,36764,30624,11224,2496,304,52,66004,
%U 55192,18624,3952,472,48,111764,97840,40008,9912,1740,244,36,175156,158280,63632,15744,2560,156,8,16
%N Irregular table read by rows: Take a diagonal-edged (or diamond-shaped) checkerboard with all diagonals drawn, as in A333434. Then T(n,k) = number of k-sided polygons in that figure for k >= 3.
%C See A333434 for the definition and images of the checkerboard.
%H Lars Blomberg, <a href="/A333458/b333458.txt">Table of n, a(n) for n = 1..201</a> (the first 27 rows)
%e Table begins:
%e 4;
%e 84, 20;
%e 692, 312, 72, 4;
%e 2708, 2020, 400, 88, 0, 4;
%e 7876, 5764, 1580, 264, 20, 4;
%e 18220, 14868, 4960, 904, 112, 24;
%e 36764, 30624, 11224, 2496, 304, 52;
%e 66004, 55192, 18624, 3952, 472, 48;
%e 111764, 97840, 40008, 9912, 1740, 244, 36;
%e 175156, 158280, 63632, 15744, 2560, 156, 8, 16;
%e ...
%Y Cf. A333434 (regions), A333459 (vertices), A333460 (edges), A331911, A331451, A333025, A333037.
%K nonn,tabf
%O 1,1
%A _Scott R. Shannon_ and _N. J. A. Sloane_, Mar 22 2020
%E a(32) and beyond from _Lars Blomberg_, Jun 03 2020