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 A302224 #4 Apr 03 2018 12:16:35 %S A302224 0,1,0,1,3,0,2,14,11,0,3,45,43,34,0,5,146,164,194,111,0,8,537,760,934, %T A302224 675,361,0,13,1934,3425,6110,4237,2666,1172,0,21,6861,15569,38736, %U A302224 40395,21777,9819,3809,0,34,24386,70323,251254,338204,292781,105585,37382 %N A302224 T(n,k)=Number of nXk 0..1 arrays with every element equal to 1, 2 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. %C A302224 Table starts %C A302224 .0.....1......1.......2.........3..........5...........8............13 %C A302224 .0.....3.....14......45.......146........537........1934..........6861 %C A302224 .0....11.....43.....164.......760.......3425.......15569.........70323 %C A302224 .0....34....194.....934......6110......38736......251254.......1610569 %C A302224 .0...111....675....4237.....40395.....338204.....3018243......26373655 %C A302224 .0...361...2666...21777....292781....3420704....42508145.....524715109 %C A302224 .0..1172...9819..105585...2043848...32181643...553097760....9458629708 %C A302224 .0..3809..37382..523414..14419536..310963650..7403262824..177191137344 %C A302224 .0.12377.140039.2578424.101511446.2973099477.97939043966.3265007473096 %H A302224 R. H. Hardin, <a href="/A302224/b302224.txt">Table of n, a(n) for n = 1..181</a> %F A302224 Empirical for column k: %F A302224 k=1: a(n) = a(n-1) %F A302224 k=2: a(n) = 3*a(n-1) +a(n-2) -2*a(n-4) %F A302224 k=3: [order 11] %F A302224 k=4: [order 30] for n>34 %F A302224 k=5: [order 92] for n>97 %F A302224 Empirical for row n: %F A302224 n=1: a(n) = a(n-1) +a(n-2) %F A302224 n=2: a(n) = 2*a(n-1) +3*a(n-2) +6*a(n-3) +10*a(n-4) +4*a(n-5) for n>6 %F A302224 n=3: [order 15] for n>17 %F A302224 n=4: [order 54] for n>58 %e A302224 Some solutions for n=5 k=4 %e A302224 ..0..0..1..1. .0..0..1..0. .0..0..1..1. .0..0..0..1. .0..0..1..1 %e A302224 ..0..1..1..1. .1..1..0..1. .0..1..0..1. .1..1..1..0. .0..1..1..1 %e A302224 ..1..0..0..0. .1..1..0..0. .1..0..0..1. .0..0..0..0. .1..0..0..0 %e A302224 ..1..1..1..1. .1..0..0..1. .1..1..1..1. .0..1..1..1. .0..0..1..1 %e A302224 ..0..0..0..0. .1..1..1..0. .0..0..0..0. .0..0..1..1. .0..0..1..1 %Y A302224 Column 2 is A180762. %Y A302224 Row 1 is A000045(n-1). %K A302224 nonn,tabl %O A302224 1,5 %A A302224 _R. H. Hardin_, Apr 03 2018