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 A205254 #7 Jul 22 2025 18:42:00 %S A205254 8752,323856,12301024,471988176,18189909484,702420750928, %T A205254 27149753088796,1049837466171440,40603753889665636, %U A205254 1570549319417597660,60751409051086135564,2350012855527394133456,90905131505907584858392 %N A205254 Number of (n+1)X8 0..1 arrays with the number of clockwise edge increases in every 2X2 subblock the same. %C A205254 Column 7 of A205255 %H A205254 R. H. Hardin, <a href="/A205254/b205254.txt">Table of n, a(n) for n = 1..210</a> %F A205254 Empirical: a(n) = 106*a(n-1) -4578*a(n-2) +110127*a(n-3) -1685691*a(n-4) +17662632*a(n-5) -132490685*a(n-6) +732439565*a(n-7) -3041749572*a(n-8) +9607185471*a(n-9) -23244897123*a(n-10) +43214022033*a(n-11) -61676422325*a(n-12) +67255934696*a(n-13) -55515488409*a(n-14) +34166147646*a(n-15) -15313024644*a(n-16) +4816467696*a(n-17) -999456992*a(n-18) +121777664*a(n-19) -6527616*a(n-20) %e A205254 Some solutions for n=4 %e A205254 ..1..0..0..1..0..1..0..1....0..1..1..0..1..1..0..1....0..1..1..0..0..0..1..1 %e A205254 ..1..1..1..1..1..1..1..1....1..1..0..0..0..0..0..0....0..0..1..0..1..0..1..0 %e A205254 ..1..0..1..0..0..0..0..0....0..0..0..1..0..1..1..0....1..1..1..0..1..1..1..0 %e A205254 ..1..1..1..0..1..1..1..0....1..0..1..1..1..1..0..0....0..0..0..0..1..0..1..1 %e A205254 ..0..1..0..0..0..1..0..0....0..0..0..0..0..1..0..1....0..1..1..0..0..0..0..0 %K A205254 nonn %O A205254 1,1 %A A205254 _R. H. Hardin_ Jan 24 2012