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 A241304 #6 Jun 02 2025 10:04:43 %S A241304 8,40,186,1462,6718,41336,217785,1215485,6526016,35833494,193952033, %T A241304 1061500415,5762495209,31479526822,171241179058,934265732146, %U A241304 5087340052649,27739343474292,151117812704114,823771403533550 %N A241304 Number of nX5 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of elements above it or zero plus the sum of the elements diagonally to its northwest or zero plus the sum of the elements antidiagonally to its northeast, modulo 4. %C A241304 Column 5 of A241306 %H A241304 R. H. Hardin, <a href="/A241304/b241304.txt">Table of n, a(n) for n = 1..21</a> %e A241304 Some solutions for n=4 %e A241304 ..3..2..3..2..3....3..2..3..2..3....3..2..3..2..3....3..2..3..2..3 %e A241304 ..1..2..1..2..3....1..2..1..2..1....3..0..1..1..3....3..0..1..2..1 %e A241304 ..3..2..2..2..2....3..0..0..2..2....1..0..2..2..2....2..1..0..2..3 %e A241304 ..2..0..0..1..2....1..0..2..0..2....1..0..2..0..2....2..3..2..2..3 %K A241304 nonn %O A241304 1,1 %A A241304 _R. H. Hardin_, Apr 18 2014