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 A269014 #7 Jan 18 2019 08:31:22 %S A269014 0,48,224,2136,10976,73568,390064,2291728,12190944,67387784,356115520, %T A269014 1906181472,9983123936,52432319344,272227610848,1412208727736, %U A269014 7276913394080,37421599567712,191604936958480,978880041945808 %N A269014 Number of 4 X n binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two exactly once. %H A269014 R. H. Hardin, <a href="/A269014/b269014.txt">Table of n, a(n) for n = 1..210</a> %F A269014 Empirical: a(n) = 4*a(n-1) + 28*a(n-2) - 78*a(n-3) - 264*a(n-4) + 296*a(n-5) + 527*a(n-6) - 252*a(n-7) - 324*a(n-8). %F A269014 Empirical g.f.: 8*x^2*(6 + 4*x - 13*x^2 - 12*x^3) / (1 - 2*x - 16*x^2 + 7*x^3 + 18*x^4)^2. - _Colin Barker_, Jan 18 2019 %e A269014 Some solutions for n=4: %e A269014 ..0..0..1..0. .0..1..0..0. .0..1..0..0. .0..1..0..0. .1..0..0..0 %e A269014 ..0..1..0..0. .0..1..0..0. .1..0..0..0. .1..0..0..0. .0..0..1..0 %e A269014 ..0..0..0..1. .0..0..0..1. .0..0..0..1. .0..0..0..0. .1..0..1..0 %e A269014 ..0..1..0..0. .1..1..0..1. .1..0..0..1. .1..0..0..0. .1..0..0..1 %Y A269014 Row 4 of A269011. %K A269014 nonn %O A269014 1,2 %A A269014 _R. H. Hardin_, Feb 17 2016