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 A189335 #8 Jul 22 2025 11:42:30 %S A189335 2,16,512,36626,6814820,2650369322,2739456017053,6190300153637745 %N A189335 Number of n X n binary arrays without the pattern 1 0 0 1 diagonally, vertically, antidiagonally or horizontally. %C A189335 Diagonal of A189343 %e A189335 Some solutions for 4X4 %e A189335 ..0..1..0..0....0..1..0..0....1..1..1..1....0..1..0..1....1..1..0..0 %e A189335 ..0..0..0..0....1..0..0..0....0..0..1..1....0..1..0..1....1..0..0..0 %e A189335 ..0..1..1..0....1..0..0..0....0..0..0..0....0..1..0..1....1..1..1..0 %e A189335 ..0..1..0..0....1..0..1..0....0..0..0..0....1..0..1..0....0..1..1..1 %K A189335 nonn %O A189335 1,1 %A A189335 _R. H. Hardin_ Apr 20 2011