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 A241135 #6 Jul 23 2025 11:11:33 %S A241135 2,17,152,1670,19619,238607,2939027,36470565,454209512,5665536042, %T A241135 70725144550,883230404813,11031990457193,137807268659287, %U A241135 1721508492588267,21505781617159089,268661629731046770 %N A241135 Number of nX4 0..2 arrays with no element equal to the same number of vertical neighbors as horizontal neighbors, with new values 0..2 introduced in row major order. %C A241135 Column 4 of A241138 %H A241135 R. H. Hardin, <a href="/A241135/b241135.txt">Table of n, a(n) for n = 1..210</a> %e A241135 Some solutions for n=4 %e A241135 ..0..1..1..1....0..0..0..1....0..0..0..1....0..0..1..1....0..0..1..1 %e A241135 ..0..2..0..0....1..1..2..1....2..2..2..1....2..2..2..2....1..1..2..2 %e A241135 ..0..2..1..1....2..2..2..2....0..2..0..0....0..1..1..1....0..2..0..1 %e A241135 ..2..2..2..2....1..1..0..0....0..2..1..1....0..2..2..2....0..2..0..1 %K A241135 nonn %O A241135 1,1 %A A241135 _R. H. Hardin_, Apr 16 2014