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 A223806 #6 Jul 23 2025 04:32:45 %S A223806 16384,268435456,400006582368,108631485025292,11005258705825234, %T A223806 584566278788358762,19618352087687868206,465158078382468013314, %U A223806 8382245182389408629393,120791502810712490663930 %N A223806 Number of 7Xn 0..3 arrays with rows and antidiagonals unimodal. %C A223806 Row 7 of A223801 %H A223806 R. H. Hardin, <a href="/A223806/b223806.txt">Table of n, a(n) for n = 1..23</a> %e A223806 Some solutions for n=3 %e A223806 ..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0 %e A223806 ..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0 %e A223806 ..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0 %e A223806 ..0..0..0....0..2..0....0..2..0....0..2..0....0..2..0....0..2..0....0..2..0 %e A223806 ..0..2..2....0..0..1....2..2..2....1..2..0....0..2..0....0..2..1....1..0..0 %e A223806 ..1..1..0....1..2..3....3..2..0....1..3..0....3..3..1....1..2..3....3..3..3 %e A223806 ..0..2..0....0..3..2....3..2..0....3..2..1....1..2..2....2..2..1....2..0..0 %K A223806 nonn %O A223806 1,1 %A A223806 _R. H. Hardin_ Mar 27 2013