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 A202737 #7 Jul 22 2025 16:48:23 %S A202737 2,6,38,86,282,1074,2802,8694,30170,82286,251682,837026,2336882, %T A202737 7101030,23060898,65306934,197740602,632536014,1808535522,5464051326, %U A202737 17297449410,49797577110,150233445162,471996750978,1365869873682,4116478752054 %N A202737 Number of nX3 0..1 arrays with row sums equal and column sums unequal to adjacent columns. %C A202737 Column 3 of A202742 %H A202737 R. H. Hardin, <a href="/A202737/b202737.txt">Table of n, a(n) for n = 1..210</a> %e A202737 Some solutions for n=5 %e A202737 ..0..1..1....1..1..0....1..0..1....0..0..1....0..1..1....1..1..0....0..0..1 %e A202737 ..0..1..1....0..1..1....0..1..1....0..0..1....1..1..0....1..1..0....0..0..1 %e A202737 ..1..1..0....1..1..0....1..0..1....0..0..1....0..1..1....0..1..1....1..0..0 %e A202737 ..0..1..1....1..1..0....1..0..1....0..1..0....1..1..0....0..1..1....0..0..1 %e A202737 ..1..1..0....0..1..1....1..1..0....0..0..1....1..0..1....0..1..1....1..0..0 %K A202737 nonn %O A202737 1,1 %A A202737 _R. H. Hardin_ Dec 23 2011