This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A355841 #13 Jan 04 2024 14:13:03 %S A355841 4,40,128,44,12,320,152,24,616,512,84,28,1240,744,120,40,1936,1928, %T A355841 372,136,8,3288,2656,616,160,4960,4500,1020,332,48,7224,6472,1424,392, %U A355841 16,9760,11064,2564,824,72,16,14144,12424,2696,856,32,18312,20604,5308,1468,328,16,24384,25392,5968,1584,160,8 %N A355841 Irregular table read by rows: T(n,k) is the number of k-sided polygons formed, for k>=3, in a square when straight line segments connect the n+1 points along each edge that divide it into n equal parts to the n+1 points on the edge on the opposite side of the square. %C A355841 This sequence is similar to A355801 but here the corner vertices of the square are also connected to points on the opposite edge. %C A355841 Up to n = 50 the maximum sided k-gon created is the 8-gon. It is plausible this is the maximum sided k-gon for all n, although this is unknown. %C A355841 See A355838 for more images of the square. %H A355841 Scott R. Shannon, <a href="/A355841/a355841.jpg">Image for n = 10</a>. %e A355841 The table begins: %e A355841 4; %e A355841 40; %e A355841 128, 44, 12; %e A355841 320, 152, 24; %e A355841 616, 512, 84, 28; %e A355841 1240, 744, 120, 40; %e A355841 1936, 1928, 372, 136, 8; %e A355841 3288, 2656, 616, 160; %e A355841 4960, 4500, 1020, 332, 48; %e A355841 7224, 6472, 1424, 392, 16; %e A355841 9760, 11064, 2564, 824, 72, 16; %e A355841 14144, 12424, 2696, 856, 32; %e A355841 18312, 20604, 5308, 1468, 328, 16; %e A355841 24384, 25392, 5968, 1584, 160, 8; %e A355841 31816, 32768, 7564, 2652, 240, 16; %e A355841 40456, 42240, 10384, 3064, 248, 24; %e A355841 49384, 59152, 15068, 4680, 704, 64; %e A355841 . %e A355841 . %Y A355841 Cf. A355838 (regions), A355839 (vertices), A355840 (edges), A355801 (without corner vertices), A290131, A331452, A335678. %K A355841 nonn,tabf %O A355841 1,1 %A A355841 _Scott R. Shannon_, Jul 18 2022