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 A223796 #6 Jul 23 2025 04:31:53 %S A223796 50,2500,110116,4816168,210163664,9169032476,400006582368, %T A223796 17450517286804,761287955888788,33211580867804324,1448872354425344280, %U A223796 63207803924281966208,2757473052802943936172,120296184397162010680224 %N A223796 Number of nX3 0..3 arrays with rows and antidiagonals unimodal. %C A223796 Column 3 of A223801 %H A223796 R. H. Hardin, <a href="/A223796/b223796.txt">Table of n, a(n) for n = 1..210</a> %F A223796 Empirical: a(n) = 50*a(n-1) -253*a(n-2) -1283*a(n-3) +8456*a(n-4) -10020*a(n-5) -12064*a(n-6) +27360*a(n-7) -6656*a(n-8) -9728*a(n-9) +4096*a(n-10) %e A223796 Some solutions for n=3 %e A223796 ..3..2..0....1..2..3....0..1..2....2..2..2....3..1..1....1..1..3....1..1..3 %e A223796 ..2..2..1....2..3..2....1..2..3....2..2..2....3..2..2....2..3..3....0..3..3 %e A223796 ..3..3..2....2..0..0....2..3..3....1..3..3....1..2..3....1..2..2....1..2..1 %K A223796 nonn %O A223796 1,1 %A A223796 _R. H. Hardin_ Mar 27 2013