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 A203655 #7 Jul 22 2025 17:25:27 %S A203655 4782969,3295578857,2843024036697,2669260624372937, %T A203655 2592476403527692089,2554890395768832271017,2533535485859974387986201, %U A203655 2519204090844384026262668425,2507880611006135260374020018937 %N A203655 1/25 the number of (n+1)X8 0..4 arrays with every 2X2 subblock having equal diagonal elements or equal antidiagonal elements. %C A203655 Column 7 of A203656 %H A203655 R. H. Hardin, <a href="/A203655/b203655.txt">Table of n, a(n) for n = 1..22</a> %e A203655 Some solutions for n=4 %e A203655 ..1..2..1..0..3..1..0..4....3..4..4..2..4..4..0..1....0..4..0..4..3..4..3..0 %e A203655 ..0..1..2..1..0..3..1..0....3..3..4..4..0..4..4..0....2..0..0..0..4..0..4..3 %e A203655 ..1..4..1..2..1..0..3..1....2..3..3..4..4..4..4..4....3..2..0..0..0..3..0..4 %e A203655 ..2..1..3..1..3..1..0..3....0..2..3..3..4..2..4..4....4..3..2..0..4..0..0..0 %e A203655 ..1..1..1..3..3..3..1..0....0..0..2..3..3..4..4..2....3..4..3..2..0..1..0..0 %K A203655 nonn %O A203655 1,1 %A A203655 _R. H. Hardin_ Jan 04 2012