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 A222875 #6 Jul 23 2025 03:11:37 %S A222875 34,26311,19707855,20978414941,16473931317022,17791003053622809, %T A222875 14337592109053271558,15577784123509878927189, %U A222875 12749920491741166976464865,13889030706696776488786035425,11487953403507942395037197786965 %N A222875 Number of nX5 0..3 arrays with no more than floor(nX5/2) elements equal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order. %C A222875 Column 5 of A222878 %H A222875 R. H. Hardin, <a href="/A222875/b222875.txt">Table of n, a(n) for n = 1..51</a> %e A222875 Some solutions for n=3 %e A222875 ..0..0..0..1..0....0..0..0..1..2....0..0..0..1..2....0..0..0..1..2 %e A222875 ..0..2..0..2..1....0..3..0..3..0....0..3..0..1..2....0..0..2..0..1 %e A222875 ..0..3..0..1..0....2..1..2..2..0....2..2..0..3..0....3..1..1..0..3 %K A222875 nonn %O A222875 1,1 %A A222875 _R. H. Hardin_ Mar 08 2013