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 A251272 #6 Jun 02 2025 10:20:18 %S A251272 1049,8812,49872,217634,790734,2510004,7189937,19018266,47251067, %T A251272 111715980,253943272,559554564,1203154060,2538190856,5276700889, %U A251272 10848708252,22120797741,44832823100,90470607368,182010260670 %N A251272 Number of (5+1)X(n+1) 0..1 arrays with no 2X2 subblock having x11-x00 less than x10-x01. %C A251272 Row 5 of A251268 %H A251272 R. H. Hardin, <a href="/A251272/b251272.txt">Table of n, a(n) for n = 1..210</a> %F A251272 Empirical: a(n) = 13*a(n-1) -77*a(n-2) +275*a(n-3) -660*a(n-4) +1122*a(n-5) -1386*a(n-6) +1254*a(n-7) -825*a(n-8) +385*a(n-9) -121*a(n-10) +23*a(n-11) -2*a(n-12) %e A251272 Some solutions for n=3 %e A251272 ..0..0..1..1....1..1..0..0....0..0..0..1....1..1..1..1....1..0..1..0 %e A251272 ..0..0..0..1....0..0..1..1....0..0..1..1....0..0..1..1....0..1..0..1 %e A251272 ..0..0..0..1....0..0..0..0....0..1..1..1....0..1..1..1....0..0..1..1 %e A251272 ..1..1..1..1....0..0..0..0....1..0..0..0....0..1..1..1....0..0..0..1 %e A251272 ..0..0..0..0....0..0..1..1....0..1..1..1....1..1..1..1....0..0..1..1 %e A251272 ..0..0..1..1....0..0..0..1....0..1..1..1....0..0..1..1....0..1..1..1 %K A251272 nonn %O A251272 1,1 %A A251272 _R. H. Hardin_, Dec 01 2014