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 A194537 #7 Jul 22 2025 12:34:45 %S A194537 1,4,132,62038,286773762,8096809998526,1243336605965267360, %T A194537 1026437889413641002431445 %N A194537 Number of lower triangles of an n X n 0..5 array with new values introduced in row major order 0..5 and no element equal to more than one horizontal or vertical neighbor. %C A194537 Column 5 of A194540 %e A194537 Some solutions for 3X3 %e A194537 ..0......0......0......0......0......0......0......0......0......0......0 %e A194537 ..1.2....1.2....1.2....1.2....1.2....1.2....0.1....1.0....1.1....0.1....0.1 %e A194537 ..2.0.3..0.2.1..3.1.1..3.2.1..3.0.1..3.4.1..1.0.1..2.0.1..0.0.2..1.0.2..1.0.0 %K A194537 nonn %O A194537 1,2 %A A194537 _R. H. Hardin_ Aug 28 2011