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 A184558 #7 Jun 02 2025 03:48:37 %S A184558 2167,91157,3436266,134840527,5228522011,203570564774,7915660174974, %T A184558 307926979784837,11976979258313503,465872448754593695, %U A184558 18120917050387510050,704848019543121767190,27416378429106168358674 %N A184558 Number of (n+1)X4 0..2 arrays with no 2X2 subblock summing to less than 4. %C A184558 Column 3 of A184564 %H A184558 R. H. Hardin, <a href="/A184558/b184558.txt">Table of n, a(n) for n = 1..200</a> %e A184558 Some solutions for 3X4 %e A184558 ..2..0..2..2....2..2..2..0....1..1..1..2....0..1..1..0....1..2..1..1 %e A184558 ..2..2..2..0....1..2..0..2....2..2..2..1....2..2..2..1....2..2..2..0 %e A184558 ..1..0..1..1....1..2..2..2....1..1..0..1....2..1..0..1....1..2..1..2 %K A184558 nonn %O A184558 1,1 %A A184558 _R. H. Hardin_ Jan 17 2011