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 A286216 #6 Apr 05 2020 20:19:52 %S A286216 0,0,0,0,4,0,0,17,17,0,0,62,52,62,0,1,238,684,684,238,1,3,912,2128, %T A286216 10056,2128,912,3,10,3468,34896,141018,141018,34896,3468,10,24,13224, %U A286216 123541,2053994,1656022,2053994,123541,13224,24,60,50655,1891998,30004158 %N A286216 T(n,k) = Number of n X k 0..1 arrays with the number of 1's king-move adjacent to some 0 two less than the number of 0's adjacent to some 1. %C A286216 Table starts %C A286216 ..0.....0.......0..........0.............0................1..................3 %C A286216 ..0.....4......17.........62...........238..............912...............3468 %C A286216 ..0....17......52........684..........2128............34896.............123541 %C A286216 ..0....62.....684......10056........141018..........2053994...........30004158 %C A286216 ..0...238....2128.....141018.......1656022........113258929.........1569283128 %C A286216 ..1...912...34896....2053994.....113258929.......6553131164.......380797680269 %C A286216 ..3..3468..123541...30004158....1569283128.....380797680269.....23594688741164 %C A286216 .10.13224.1891998..443275636...97311031516...22418184755710...5201563721481604 %C A286216 .24.50655.7565509.6591532114.1540259241508.1330080388106827.366234192215237315 %H A286216 R. H. Hardin, <a href="/A286216/b286216.txt">Table of n, a(n) for n = 1..161</a> %e A286216 Some solutions for n=4, k=4 %e A286216 ..0..1..1..0. .0..0..0..0. .1..0..1..1. .0..0..1..0. .1..1..1..1 %e A286216 ..0..0..0..1. .0..1..1..1. .0..0..0..0. .1..0..0..0. .0..0..0..1 %e A286216 ..1..1..1..0. .1..1..0..0. .1..1..1..0. .1..0..0..1. .0..0..0..0 %e A286216 ..0..1..0..0. .1..0..1..0. .1..0..0..0. .0..1..1..1. .0..0..1..0 %K A286216 nonn,tabl %O A286216 1,5 %A A286216 _R. H. Hardin_, May 04 2017