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 A267789 #4 Jan 20 2016 12:31:59 %S A267789 6,36,216,1056,5004,22110,94554,391314,1582824,6278400,24520080, %T A267789 94523100,360449622,1361930880,5105718624,19011717024,70378031196, %U A267789 259193957658,950281765146,3470120581542,12626754295920,45799000309176 %N A267789 Number of 3Xn 0..1 arrays with every repeated value in every row greater than or equal to, and in every column greater than, the previous repeated value. %C A267789 Row 3 of A267788. %H A267789 R. H. Hardin, <a href="/A267789/b267789.txt">Table of n, a(n) for n = 1..210</a> %F A267789 Empirical: a(n) = 8*a(n-1) -12*a(n-2) -40*a(n-3) +80*a(n-4) +100*a(n-5) -134*a(n-6) -160*a(n-7) +8*a(n-8) +48*a(n-9) +8*a(n-10) -4*a(n-11) -a(n-12) %e A267789 Some solutions for n=4 %e A267789 ..0..0..1..0....0..1..0..1....0..0..1..1....0..1..0..1....1..1..0..1 %e A267789 ..0..1..1..1....1..0..1..1....1..1..1..1....1..0..1..0....1..0..1..1 %e A267789 ..1..0..0..0....1..0..1..0....1..0..0..0....0..0..0..1....0..1..1..0 %Y A267789 Cf. A267788. %K A267789 nonn %O A267789 1,1 %A A267789 _R. H. Hardin_, Jan 20 2016