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 A233154 #8 Oct 08 2018 10:21:03 %S A233154 192,5832,184248,5871528,187446312,5986203912,191184793128, %T A233154 6106045615848,195014812167432,6228382893621192,198922099117492008, %U A233154 6353174267751532968,202907688630068868552,6480466044680473473672,206973133655395034550888 %N A233154 Number of n X 7 0..2 arrays with no element x(i,j) adjacent to value 2-x(i,j) horizontally or antidiagonally. %H A233154 R. H. Hardin, <a href="/A233154/b233154.txt">Table of n, a(n) for n = 1..210</a> %F A233154 Empirical: a(n) = 42*a(n-1) - 351*a(n-2) + 972*a(n-3) - 810*a(n-4). %F A233154 Empirical g.f.: 24*x*(8 - 93*x + 279*x^2 - 270*x^3) / ((1 - 3*x)*(1 - 39*x + 234*x^2 - 270*x^3)). - _Colin Barker_, Oct 08 2018 %e A233154 Some solutions for n=2: %e A233154 ..0..0..1..0..1..2..1....1..2..1..0..1..2..2....2..2..1..2..2..1..0 %e A233154 ..1..0..1..2..2..2..2....2..2..1..2..1..2..1....2..2..2..1..2..1..2 %Y A233154 Column 7 of A233155. %K A233154 nonn %O A233154 1,1 %A A233154 _R. H. Hardin_, Dec 05 2013