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 A251267 #6 Jun 02 2025 10:20:04 %S A251267 1013,8277,73805,715685,7189937,73607411,760734085,7901650053, %T A251267 82288916360,858174176431,8956460879354,93513621828339, %U A251267 976584141141835,10199930967838789,106540252006060732,1112874401391136229 %N A251267 Number of (n+1)X(7+1) 0..1 arrays with no 2X2 subblock having x11-x00 less than x10-x01. %C A251267 Column 7 of A251268 %H A251267 R. H. Hardin, <a href="/A251267/b251267.txt">Table of n, a(n) for n = 1..210</a> %e A251267 Some solutions for n=3 %e A251267 ..0..1..0..1..1..1..0..0....0..0..0..0..1..0..1..1....1..0..1..1..1..0..0..1 %e A251267 ..0..0..1..0..0..0..1..1....0..0..1..1..0..1..1..1....0..1..0..0..0..1..1..1 %e A251267 ..0..0..0..1..1..1..1..1....0..1..0..0..1..0..1..1....0..0..1..1..1..0..0..1 %e A251267 ..0..0..1..0..0..0..1..1....0..0..1..1..0..1..0..1....0..0..0..0..0..1..1..1 %K A251267 nonn %O A251267 1,1 %A A251267 _R. H. Hardin_, Dec 01 2014