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 A181221 #5 Jul 22 2025 08:36:41 %S A181221 24,576,6475,97764,1495392,21513936,316896477,4672517426,68571093673, %T A181221 1008146803248,14823077688569,217869625616208,3202690847200999, %U A181221 47079980407589036,692062815855417554,10173239318638447266 %N A181221 Number of nX5 binary matrices with no three 1's adjacent in a line horizontally, vertically, diagonally or antidiagonally. %C A181221 Column 5 of A181224 %H A181221 R. H. Hardin, <a href="/A181221/b181221.txt">Table of n, a(n) for n=1..225</a> %e A181221 Some avoided solutions for 3X5 %e A181221 ..0..1..0..0..0....0..1..0..0..0....0..0..0..0..0....0..0..0..0..1 %e A181221 ..0..0..1..0..0....0..1..0..0..0....0..0..0..0..0....0..0..0..1..0 %e A181221 ..1..0..0..1..0....0..1..0..1..0....1..1..1..1..0....1..0..1..0..0 %K A181221 nonn %O A181221 1,1 %A A181221 _R. H. Hardin_ Oct 10 2010