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 A238320 #6 Jul 23 2025 10:51:50 %S A238320 121,9489,405636,13265123,459256128,17315827838,658399071392, %T A238320 24577532667851,910817281935043,33837788379096408,1260231451310023356, %U A238320 46939033254320776972,1747281376213884382709,65029646539397230908874 %N A238320 Number of (n+1)X(5+1) 0..2 arrays with no element greater than all horizontal neighbors or less than all vertical neighbors. %C A238320 Column 5 of A238323 %H A238320 R. H. Hardin, <a href="/A238320/b238320.txt">Table of n, a(n) for n = 1..210</a> %e A238320 Some solutions for n=2 %e A238320 ..2..2..0..1..2..2....1..1..1..1..0..0....1..1..1..1..1..1....2..2..2..1..1..0 %e A238320 ..0..0..0..0..2..2....1..1..1..1..0..0....1..1..1..0..1..1....2..2..2..1..1..0 %e A238320 ..0..0..0..0..2..2....1..1..1..2..2..1....2..2..2..0..2..2....2..2..2..2..1..0 %K A238320 nonn %O A238320 1,1 %A A238320 _R. H. Hardin_, Feb 24 2014