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 A224177 #7 Mar 18 2025 20:56:31 %S A224177 84,7056,282372,6425876,95808564,1038484760,8857798353,63080505999, %T A224177 391482575333,2182020084219,11154302333669,53070835890575, %U A224177 237508827855216,1007614860280386,4076458517196412,15801076345180104,58906922067133096,211885437690782790,737309735186245955 %N A224177 Number of 6 X n 0..3 arrays with rows, diagonals and antidiagonals unimodal and columns nondecreasing. %H A224177 R. H. Hardin, <a href="/A224177/b224177.txt">Table of n, a(n) for n = 1..39</a> %e A224177 Some solutions for n=3: %e A224177 ..0..0..1....2..0..0....1..0..0....1..0..0....0..0..0....0..0..0....0..0..1 %e A224177 ..0..2..2....2..0..0....1..2..1....1..0..0....0..0..0....1..0..0....0..2..2 %e A224177 ..2..2..3....2..3..0....1..2..2....2..2..0....0..1..2....1..1..2....0..2..2 %e A224177 ..3..3..3....2..3..1....2..2..2....2..3..1....2..2..2....2..3..2....0..2..3 %e A224177 ..3..3..3....2..3..2....2..2..2....3..3..3....3..2..2....2..3..2....1..2..3 %e A224177 ..3..3..3....2..3..3....2..3..3....3..3..3....3..2..2....3..3..2....1..2..3 %Y A224177 Row 6 of A224173. %K A224177 nonn %O A224177 1,1 %A A224177 _R. H. Hardin_, Mar 31 2013 %E A224177 Name corrected by _Andrew Howroyd_, Mar 18 2025