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 A208697 #7 Jul 22 2025 21:28:23 %S A208697 35,1225,8977,109599,1103081,12014735,126827983,1356513169, %T A208697 14425723357,153741350353,1637205937955,17441454604351, %U A208697 185777794829329,1978904120738349,21078662513667499,224526113423385269 %N A208697 Number of nX7 0..1 arrays avoiding 0 0 1 and 1 0 0 horizontally and 0 1 0 and 1 0 1 vertically. %C A208697 Column 7 of A208698 %H A208697 R. H. Hardin, <a href="/A208697/b208697.txt">Table of n, a(n) for n = 1..210</a> %e A208697 Some solutions for n=4 %e A208697 ..0..0..0..0..0..0..0....1..1..1..1..0..1..0....0..0..0..0..0..0..0 %e A208697 ..1..0..1..1..0..1..1....0..1..0..1..0..1..0....0..0..0..0..0..0..0 %e A208697 ..1..1..1..1..0..1..1....0..0..0..0..0..0..0....1..0..1..0..1..1..0 %e A208697 ..1..1..0..1..0..1..0....1..0..1..0..1..0..1....1..1..1..1..1..1..1 %K A208697 nonn %O A208697 1,1 %A A208697 _R. H. Hardin_ Mar 01 2012