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 A207350 #7 Jul 24 2025 19:38:22 %S A207350 26,676,2812,11230,41112,128292,388134,1134282,3225374,9002616, %T A207350 24769666,67483434,182349814,489763956,1309361216,3487680090, %U A207350 9264546642,24556015282,64977975688,171714994844,453323511688,1195826552876 %N A207350 Number of 6Xn 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 0 and 1 1 1 vertically. %C A207350 Row 6 of A207346 %H A207350 R. H. Hardin, <a href="/A207350/b207350.txt">Table of n, a(n) for n = 1..210</a> %e A207350 Some solutions for n=4 %e A207350 ..1..0..1..0....0..1..0..1....1..0..0..1....0..1..0..1....0..1..0..1 %e A207350 ..0..1..0..0....1..0..1..0....0..1..0..0....1..1..1..0....1..0..0..1 %e A207350 ..0..1..0..1....1..1..0..1....1..0..1..0....0..0..1..0....1..1..1..0 %e A207350 ..1..0..1..0....0..1..0..1....1..1..1..1....0..1..0..1....0..1..0..0 %e A207350 ..0..1..0..1....0..0..1..0....0..1..0..1....1..1..0..1....1..0..0..1 %e A207350 ..1..0..0..1....1..0..1..0....0..0..1..0....1..0..1..0....1..1..1..0 %K A207350 nonn %O A207350 1,1 %A A207350 _R. H. Hardin_ Feb 17 2012