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 A219309 #5 Jul 11 2023 08:06:51 %S A219309 37,1157,43725,1574278,54797587,1935133104,68906619754,2448261182674, %T A219309 86782430779997 %N A219309 Unchanging value maps: number of n X 7 binary arrays indicating the locations of corresponding elements unequal to no horizontal or vertical neighbor in a random 0..2 n X 7 array. %C A219309 Column 7 of A219310. %e A219309 Some solutions for n=3 %e A219309 ..0..0..1..0..0..0..0....1..1..1..0..0..0..1....0..0..0..1..1..0..1 %e A219309 ..0..0..0..0..1..0..0....0..1..1..0..0..0..1....0..0..0..0..0..0..0 %e A219309 ..1..0..0..0..1..0..0....0..0..1..1..0..0..1....0..1..0..1..0..0..0 %Y A219309 Cf. A219310. %K A219309 nonn %O A219309 1,1 %A A219309 _R. H. Hardin_, Nov 17 2012