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 A207567 #7 Jul 22 2025 20:35:45 %S A207567 22,484,1690,6709,36426,138017,493471,1980774,7259428,25276248, %T A207567 91512891,323438636,1108858657,3843873169,13238517646,44841691184, %U A207567 152090405602,514775385341,1726736775278,5782478579121,19341544402175,64371828667182 %N A207567 Number of 6Xn 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically. %C A207567 Row 6 of A207564 %H A207567 R. H. Hardin, <a href="/A207567/b207567.txt">Table of n, a(n) for n = 1..210</a> %F A207567 Empirical: a(n) = 5*a(n-1) -6*a(n-2) +30*a(n-3) -117*a(n-4) +51*a(n-5) -132*a(n-6) +648*a(n-7) +291*a(n-8) -63*a(n-9) -1806*a(n-10) -1320*a(n-11) +45*a(n-12) +2859*a(n-13) +2046*a(n-14) +198*a(n-15) -1821*a(n-16) -1203*a(n-17) -294*a(n-18) +480*a(n-19) +153*a(n-20) -21*a(n-21) -78*a(n-22) +18*a(n-23) +19*a(n-24) +19*a(n-25) %e A207567 Some solutions for n=4 %e A207567 ..1..1..0..0....1..0..1..1....0..1..1..1....1..0..0..0....0..1..1..1 %e A207567 ..1..1..1..1....1..0..0..0....0..1..1..0....0..0..0..0....1..0..1..1 %e A207567 ..1..1..0..0....1..1..0..0....0..1..1..1....1..1..1..1....0..1..1..1 %e A207567 ..1..1..0..0....1..0..1..1....0..1..1..0....0..0..0..0....1..0..1..1 %e A207567 ..1..1..0..0....1..1..0..0....0..1..1..1....1..1..1..1....0..1..1..1 %e A207567 ..1..1..1..0....1..0..0..0....0..1..1..0....0..0..0..0....1..0..1..1 %K A207567 nonn %O A207567 1,1 %A A207567 _R. H. Hardin_ Feb 18 2012