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 A184561 #7 Jun 02 2025 03:48:55 %S A184561 603249,390354307,203570564774,115000791536877,63392707611948281, %T A184561 35245029137091490532,19540724845064600039882, %U A184561 10844219595929643673506107,6016136514697924805072162487,3337980836583341810657426070927 %N A184561 Number of (n+1)X7 0..2 arrays with no 2X2 subblock summing to less than 4. %C A184561 Column 6 of A184564 %H A184561 R. H. Hardin, <a href="/A184561/b184561.txt">Table of n, a(n) for n = 1..200</a> %e A184561 Some solutions for 3X7 %e A184561 ..0..0..0..2..0..2..0....0..0..0..2..1..1..2....0..0..0..2..0..2..2 %e A184561 ..2..2..2..0..2..2..0....2..2..2..0..2..2..0....2..2..2..0..2..1..2 %e A184561 ..2..0..0..2..0..1..1....1..0..2..1..1..1..2....0..0..1..2..2..2..0 %K A184561 nonn %O A184561 1,1 %A A184561 _R. H. Hardin_ Jan 17 2011