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 A209732 #7 Jul 22 2025 21:55:48 %S A209732 3912,86744,1995752,47572464,1138541280,27425792944,660346502176, %T A209732 15926642688032,383927816903616,9260294185296568,223295813816665920, %U A209732 5385580739872287984,129876262463016021256,3132320639165421379936 %N A209732 1/4 the number of (n+1)X5 0..3 arrays with every 2X2 subblock having distinct edge sums. %C A209732 Column 4 of A209736 %H A209732 R. H. Hardin, <a href="/A209732/b209732.txt">Table of n, a(n) for n = 1..210</a> %e A209732 Some solutions for n=4 %e A209732 ..0..1..0..1..3....3..3..0..0..3....2..1..1..1..0....1..0..0..0..0 %e A209732 ..3..3..2..2..3....1..2..2..1..1....3..3..0..3..0....3..2..3..1..2 %e A209732 ..0..1..0..1..1....3..3..0..0..3....0..2..2..3..2....1..0..3..0..2 %e A209732 ..0..2..0..2..3....0..1..1..2..2....0..1..0..3..0....2..2..2..0..1 %e A209732 ..3..2..3..2..0....3..3..0..0..1....2..2..0..1..0....1..0..3..3..3 %K A209732 nonn %O A209732 1,1 %A A209732 _R. H. Hardin_ Mar 12 2012