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 A228666 #10 Apr 25 2023 07:49:16 %S A228666 64,169,9598,63688,1720343,17074988,337258048,4073313193,69400592022, %T A228666 925095934000,14659747315671,205401189207844,3139657337791256, %U A228666 45112454177593993,677231112691330078,9855259627789459448 %N A228666 Number of 7 X n binary arrays with top left value 1 and no two ones adjacent horizontally, diagonally or antidiagonally. %C A228666 Row 7 of A228660. %H A228666 R. H. Hardin, <a href="/A228666/b228666.txt">Table of n, a(n) for n = 1..210</a> %F A228666 Empirical: a(n) = 9*a(n-1) +184*a(n-2) -1201*a(n-3) -7155*a(n-4) +46048*a(n-5) +70745*a(n-6) -591673*a(n-7) -154744*a(n-8) +3207657*a(n-9) -715173*a(n-10) -7580648*a(n-11) +3369552*a(n-12) +7114920*a(n-13) -3800952*a(n-14) -1923264*a(n-15) +1083456*a(n-16). %e A228666 Some solutions for n=4 %e A228666 ..1..0..0..1....1..0..0..1....1..0..0..0....1..0..0..0....1..0..0..0 %e A228666 ..1..0..0..1....1..0..0..0....0..0..1..0....1..0..0..0....1..0..0..1 %e A228666 ..0..0..0..0....0..0..0..1....1..0..0..0....0..0..0..1....0..0..0..0 %e A228666 ..0..0..0..0....1..0..0..1....1..0..1..0....1..0..0..0....0..1..0..0 %e A228666 ..0..0..0..0....0..0..0..0....1..0..0..0....0..0..0..1....0..1..0..0 %e A228666 ..0..0..0..1....0..1..0..0....0..0..0..1....0..0..0..1....0..0..0..1 %e A228666 ..1..0..0..1....0..1..0..0....1..0..0..0....0..0..0..1....1..0..0..0 %Y A228666 Cf. A228660. %K A228666 nonn %O A228666 1,1 %A A228666 _R. H. Hardin_, Aug 29 2013