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 A188500 #8 Jul 22 2025 11:13:42 %S A188500 2,16,229,5626,317751,47153387,15602080066,10679333746605, %T A188500 15965188461370862,54469837118110826481,418222453639358665952917, %U A188500 7076429422309098758072976354,264209106726567934754362229986426 %N A188500 Number of n X n binary arrays without the pattern 0 1 0 diagonally, vertically or horizontally. %C A188500 Diagonal of A188508 %e A188500 Some solutions for 3X3 %e A188500 ..1..1..1....1..1..1....1..0..1....0..0..0....0..0..1....0..0..1....1..0..0 %e A188500 ..1..1..1....0..0..0....1..0..0....1..0..0....0..0..0....0..0..1....1..0..1 %e A188500 ..0..0..1....1..1..1....0..0..0....1..1..1....0..0..0....1..1..0....1..1..1 %K A188500 nonn %O A188500 1,1 %A A188500 _R. H. Hardin_ Apr 02 2011