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 A219683 #6 Jul 23 2025 00:36:04 %S A219683 15,22,208,1531,8964,44816,220182,1116208,5697556,28354294,135630422, %T A219683 623221049,2761665622,11842133497,49237357701,198775751684, %U A219683 780253085746,2982381614057,11117260746432,40470971856226,144060818799022 %N A219683 Number of nX5 arrays of the minimum value of corresponding elements and their horizontal, vertical or antidiagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 nX5 array. %C A219683 Column 5 of A219686 %H A219683 R. H. Hardin, <a href="/A219683/b219683.txt">Table of n, a(n) for n = 1..150</a> %e A219683 Some solutions for n=3 %e A219683 ..1..0..0..0..0....2..0..0..0..0....1..1..0..0..0....2..0..0..0..0 %e A219683 ..1..0..0..0..0....2..0..0..0..0....1..0..0..0..0....2..0..0..0..0 %e A219683 ..2..2..1..0..0....2..2..0..0..0....1..0..0..2..2....2..1..1..1..1 %K A219683 nonn %O A219683 1,1 %A A219683 _R. H. Hardin_ Nov 25 2012