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 A219135 #7 Jul 23 2025 00:15:44 %S A219135 1,6,78,1774,101600,12867295,3862325048,2678391894154 %N A219135 Unchanging value maps: number of n X n binary arrays indicating the locations of corresponding elements unequal to no horizontal, diagonal or antidiagonal neighbor in a random 0..2 n X n array. %C A219135 Diagonal of A219142 %e A219135 Some solutions for n=3 %e A219135 ..1..0..1....1..0..1....0..0..0....0..0..1....0..0..1....0..0..0....1..0..0 %e A219135 ..0..0..0....0..0..1....0..0..0....0..0..1....0..0..0....0..1..0....1..0..0 %e A219135 ..0..0..0....1..0..0....1..0..0....0..0..1....1..0..0....1..1..1....0..0..1 %K A219135 nonn %O A219135 1,2 %A A219135 _R. H. Hardin_ Nov 12 2012