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Irregular table read by rows: Take a triangle with Pythagorean triple leg lengths with all diagonals drawn, as in A332978. Then T(n,k) = number of k-sided polygons in that figure for k >= 3 where the legs are divided into unit length parts.
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%I #17 Aug 24 2020 10:20:15

%S 139,94,34,3,1,2383,2421,760,167,13,2,5307,5958,2113,563,80,17,2,

%T 13083,13560,4479,1002,153,16,1,18827,20896,8256,2139,377,49,6,1,

%U 42992,45400,15930,3771,579,60,5,63526,79275,28922,7315,1404,202,14,4

%N Irregular table read by rows: Take a triangle with Pythagorean triple leg lengths with all diagonals drawn, as in A332978. Then T(n,k) = number of k-sided polygons in that figure for k >= 3 where the legs are divided into unit length parts.

%C See A332978 for the Pythagorean triple ordering and the links for images of the triangles.

%H Lars Blomberg, <a href="/A333135/b333135.txt">Table of n, a(n) for n = 1..213</a> (the first 24 rows)

%e Table begins:

%e 139, 94, 34, 3, 1;

%e 2383, 2421, 760, 167, 13, 2;

%e 5307, 5958, 2113, 563, 80, 17, 2;

%e 13083, 13560, 4479, 1002, 153, 16, 1;

%e 18827, 20896, 8256, 2139, 377, 49, 6, 1;

%e 42992, 45400, 15930, 3771, 579, 60, 5;

%e 63526, 79275, 28922, 7315, 1404, 202, 14, 4;

%e The row sums are A332978.

%Y Cf. A332978 (regions), A333136 (vertices), A333137 (edges), A103605 (Pythagorean triple ordering), A007678, A092867, A331452.

%K nonn,tabf

%O 1,1

%A _Scott R. Shannon_ and _N. J. A. Sloane_, Mar 09 2020

%E Corrected typo in a(12) and a(49) and beyond from _Lars Blomberg_, Jun 07 2020