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 A297314 #4 Dec 28 2017 07:27:54 %S A297314 1,2,1,4,7,1,7,23,21,1,12,66,117,65,1,21,207,497,609,200,1,37,654, %T A297314 2577,3808,3159,616,1,65,2049,13937,35476,29212,16389,1897,1,114,6422, %U A297314 72541,340825,484808,223995,85041,5842,1,200,20119,375054,2997197,8273245 %N A297314 T(n,k)=Number of nXk 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 1 or 2 neighboring 1s. %C A297314 Table starts %C A297314 .1.....2.......4.........7..........12............21..............37 %C A297314 .1.....7......23........66.........207...........654............2049 %C A297314 .1....21.....117.......497........2577.........13937...........72541 %C A297314 .1....65.....609......3808.......35476........340825.........2997197 %C A297314 .1...200....3159.....29212......484808.......8273245.......121339476 %C A297314 .1...616...16389....223995.....6623719.....200646607......4893232934 %C A297314 .1..1897...85041...1717882....90535227....4869858862....197589351469 %C A297314 .1..5842..441225..13174266..1237278512..118156684121...7976248015498 %C A297314 .1.17991.2289339.101033369.16909630099.2867120332406.322003901582689 %H A297314 R. H. Hardin, <a href="/A297314/b297314.txt">Table of n, a(n) for n = 1..447</a> %F A297314 Empirical for column k: %F A297314 k=1: a(n) = a(n-1) %F A297314 k=2: a(n) = 2*a(n-1) +3*a(n-2) +a(n-3) %F A297314 k=3: a(n) = 3*a(n-1) +11*a(n-2) +3*a(n-3) -6*a(n-4) %F A297314 k=4: [order 8] for n>9 %F A297314 k=5: [order 12] for n>14 %F A297314 k=6: [order 22] for n>25 %F A297314 k=7: [order 35] for n>39 %F A297314 Empirical for row n: %F A297314 n=1: a(n) = 2*a(n-1) -a(n-2) +a(n-3) %F A297314 n=2: [order 9] %F A297314 n=3: [order 23] %F A297314 n=4: [order 61] %e A297314 Some solutions for n=5 k=4 %e A297314 ..0..1..1..1. .1..1..0..0. .1..1..1..0. .0..1..0..0. .0..0..1..0 %e A297314 ..1..0..0..0. .0..0..0..1. .0..0..1..0. .1..1..1..1. .1..1..0..0 %e A297314 ..0..1..0..1. .0..0..1..0. .0..1..1..0. .0..0..0..1. .0..0..0..1 %e A297314 ..1..1..1..0. .0..0..1..0. .0..1..0..0. .0..0..1..1. .0..1..1..0 %e A297314 ..0..0..0..0. .0..1..1..1. .0..1..1..1. .0..0..1..1. .1..0..1..1 %Y A297314 Column 2 is A218836. %Y A297314 Row 1 is A005251(n+2). %K A297314 nonn,tabl %O A297314 1,2 %A A297314 _R. H. Hardin_, Dec 28 2017