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 A207492 #7 Jul 22 2025 20:29:54 %S A207492 35,1225,2233,11306,39050,89417,268275,667760,1691526,4324858, %T A207492 10910668,28038606,71784122,186198243,482642047,1259170885,3300248079, %U A207492 8616047712,22660486326,59449698479,156019165327,410863919802,1077513243234 %N A207492 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 1 1 and 1 1 0 vertically. %C A207492 Row 7 of A207488 %H A207492 R. H. Hardin, <a href="/A207492/b207492.txt">Table of n, a(n) for n = 1..210</a> %e A207492 Some solutions for n=4 %e A207492 ..1..1..1..1....0..1..0..0....0..0..1..0....0..1..0..0....1..1..0..1 %e A207492 ..0..0..1..0....0..1..0..0....1..1..0..0....0..1..0..1....0..1..0..1 %e A207492 ..0..0..1..0....0..1..0..0....0..0..1..0....1..1..1..0....1..1..1..1 %e A207492 ..1..1..1..1....0..1..0..1....0..1..0..0....0..1..0..0....0..1..0..1 %e A207492 ..0..0..1..0....1..1..0..0....1..0..0..1....0..1..0..0....0..1..0..1 %e A207492 ..0..0..1..0....0..1..0..1....0..0..1..0....1..1..1..0....0..1..0..1 %e A207492 ..0..0..1..0....0..1..0..0....1..1..0..0....0..1..0..0....0..1..0..1 %K A207492 nonn %O A207492 1,1 %A A207492 _R. H. Hardin_ Feb 18 2012