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 A207922 #7 Jul 22 2025 21:00:18 %S A207922 42,1764,12994,101069,628945,4105063,28188778,187980955,1245595210, %T A207922 8342244698,55794408879,372138707621,2485175186365,16603501309984, %U A207922 110873077840653,740391497518318,4944900311857882,33024243581797845 %N A207922 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 1 0 and 1 0 1 vertically. %C A207922 Row 7 of A207918 %H A207922 R. H. Hardin, <a href="/A207922/b207922.txt">Table of n, a(n) for n = 1..210</a> %e A207922 Some solutions for n=4 %e A207922 ..1..0..0..1....1..0..0..1....0..1..0..0....0..1..1..0....0..1..0..0 %e A207922 ..0..1..1..0....1..0..0..1....1..1..1..0....0..0..1..0....0..0..1..0 %e A207922 ..0..1..1..0....0..0..1..1....1..1..1..1....0..0..1..1....0..0..1..0 %e A207922 ..1..1..1..1....0..1..1..0....1..0..0..1....1..0..0..1....1..0..0..1 %e A207922 ..1..0..0..1....0..1..0..0....1..0..0..1....1..1..0..0....1..0..0..1 %e A207922 ..1..0..0..1....1..0..0..1....0..0..1..0....0..1..1..0....1..0..0..1 %e A207922 ..1..1..1..0....1..0..0..1....0..0..1..0....0..1..1..0....1..0..0..1 %K A207922 nonn %O A207922 1,1 %A A207922 _R. H. Hardin_ Feb 21 2012