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 A222453 #6 Jul 23 2025 02:36:39 %S A222453 4,10,27,426,1847,16440,84558,910358,4757427,51324484,271866564, %T A222453 2984245628,15890235207,175650675430,939482925840,10439882627616, %U A222453 56035969028768,625001788261676,3364621225556746,37635020888605163 %N A222453 Number of nX5 0..1 arrays with exactly floor(nX5/2) elements unequal to at least one horizontal, vertical or antidiagonal neighbor, with new values introduced in row major 0..1 order. %C A222453 Column 5 of A222456 %H A222453 R. H. Hardin, <a href="/A222453/b222453.txt">Table of n, a(n) for n = 1..121</a> %e A222453 Some solutions for n=4 %e A222453 ..0..0..0..1..0....0..0..0..0..0....0..1..0..1..1....0..0..0..0..0 %e A222453 ..0..0..0..0..0....0..0..1..0..0....0..1..1..1..1....0..0..0..0..0 %e A222453 ..0..0..1..0..0....1..0..0..0..0....0..1..1..1..1....0..0..0..0..0 %e A222453 ..0..0..0..0..0....0..0..0..0..0....1..1..1..1..1....1..1..0..1..0 %K A222453 nonn %O A222453 1,1 %A A222453 _R. H. Hardin_ Feb 20 2013