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 A342132 #12 Apr 18 2021 01:46:43 %S A342132 1,1,0,1,1,2,3,7,12,28,54,127,266,614,1356,3134,7091,16482,37929, %T A342132 88622,206295,484445,1136897,2682451,6333249,15005945,35595805, %U A342132 84649515,201560350,480845007,1148537092,2747477575,6579923491,15777658535,37871501929 %N A342132 Number of unlabeled vertically indecomposable modular lattices on n nodes. %C A342132 A lattice is vertically decomposable if it has an element that is comparable to all elements and is neither the bottom nor the top element. Otherwise the lattice is vertically indecomposable. %H A342132 P. Jipsen and N. Lawless, <a href="https://doi.org/10.1007/s00012-015-0348-x">Generating all finite modular lattices of a given size</a>, Algebra universalis, 74 (2015), 253-264. %H A342132 J. Kohonen, <a href="https://doi.org/10.1007/s11083-018-9475-2">Generating modular lattices of up to 30 elements</a>, Order, 36 (2019), 423-435. %H A342132 J. Kohonen, <a href="https://arxiv.org/abs/2007.03232">Cartesian lattice counting by the vertical 2-sum</a>, arXiv:2007.03232 [math.CO] preprint (2020). %e A342132 a(7)=3: These are the three lattices. %e A342132 o o __o__ %e A342132 / \ /|\ / /|\ \ %e A342132 o o o o o o o o o o %e A342132 /|\ / / \|/ \_\|/_/ %e A342132 o o o o o o %e A342132 \|/ \ / %e A342132 o o %Y A342132 Cf. A006981 (modular lattices, including vertically decomposable). %K A342132 nonn %O A342132 1,6 %A A342132 _Jukka Kohonen_, Mar 01 2021