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 A228505 #7 Sep 01 2013 17:49:36 %S A228505 13,43,684,4749,49101,413786,3862849,34229311,311423874,2795565191, %T A228505 25267110999,227577191098,2053397764249,18510745379063, %U A228505 166945846438154,1505305762277273,13574575402532525,122405516285033798 %N A228505 Number of nX7 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically, diagonally or antidiagonally. %C A228505 Column 7 of A228506 %H A228505 R. H. Hardin, <a href="/A228505/b228505.txt">Table of n, a(n) for n = 1..210</a> %F A228505 Empirical: a(n) = 6*a(n-1) +50*a(n-2) -171*a(n-3) -514*a(n-4) +1800*a(n-5) +845*a(n-6) -5430*a(n-7) +704*a(n-8) +6175*a(n-9) -1762*a(n-10) -2810*a(n-11) +870*a(n-12) +392*a(n-13) -120*a(n-14) %e A228505 Some solutions for n=4 %e A228505 ..1..0..0..1..0..0..0....1..0..0..0..0..0..1....1..0..1..0..1..0..0 %e A228505 ..0..0..0..0..0..0..0....0..0..0..0..0..0..0....0..0..0..0..0..0..1 %e A228505 ..0..1..0..0..0..0..0....1..0..0..0..0..0..1....1..0..1..0..0..0..0 %e A228505 ..0..0..0..0..0..1..0....0..0..1..0..1..0..0....0..0..0..0..0..1..0 %K A228505 nonn %O A228505 1,1 %A A228505 _R. H. Hardin_ Aug 23 2013