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 A240288 #6 Jun 02 2025 09:47:02 %S A240288 7,114,1461,33183,484146,13490093,224906182,6988931041,124429466670, %T A240288 4051638112330,74018226541069,2452262844599318,45215487411950078, %U A240288 1507127744748116582,27877553829380592951,931147017328796104053 %N A240288 Number of 5Xn 0..3 arrays with no element equal to one plus the sum of elements to its left or two plus the sum of the elements above it or zero plus the sum of the elements diagonally to its northwest, modulo 4. %C A240288 Row 5 of A240284 %H A240288 R. H. Hardin, <a href="/A240288/b240288.txt">Table of n, a(n) for n = 1..210</a> %e A240288 Some solutions for n=4 %e A240288 ..3..3..1..1....3..3..1..3....3..3..1..3....3..1..3..3....3..1..3..1 %e A240288 ..3..2..1..2....2..2..0..0....3..2..0..0....2..2..2..2....3..1..3..1 %e A240288 ..2..2..2..2....2..1..2..0....3..1..2..0....2..0..2..2....3..2..3..3 %e A240288 ..3..3..0..2....3..3..0..2....2..2..2..2....3..3..0..0....2..0..2..2 %e A240288 ..3..2..3..2....2..2..0..0....3..1..2..1....2..2..0..3....2..1..2..0 %K A240288 nonn %O A240288 1,1 %A A240288 _R. H. Hardin_, Apr 03 2014