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 A224154 #6 Jul 23 2025 05:00:57 %S A224154 11,56,187,574,1783,5657,18408,61140,205390,694018,2350061,7961090, %T A224154 26964678,91303265,309082754,1046163241,3540718751,11983122960, %U A224154 40555030532,137252283821,464510611475,1572073476421,5320479934245 %N A224154 Number of nX4 0..1 arrays with diagonals and rows unimodal and antidiagonals nondecreasing. %C A224154 Column 4 of A224158 %H A224154 R. H. Hardin, <a href="/A224154/b224154.txt">Table of n, a(n) for n = 1..210</a> %F A224154 Empirical: a(n) = 5*a(n-1) -5*a(n-2) -2*a(n-3) -3*a(n-4) +18*a(n-5) -18*a(n-6) +27*a(n-7) -3*a(n-8) -4*a(n-9) -8*a(n-11) -6*a(n-12) -6*a(n-13) for n>14 %e A224154 Some solutions for n=3 %e A224154 ..0..0..0..0....1..1..0..0....1..1..1..0....1..1..1..1....0..1..0..0 %e A224154 ..1..0..0..0....1..1..0..0....1..1..0..0....1..1..1..1....1..1..1..0 %e A224154 ..1..1..1..1....1..1..1..0....1..1..1..0....1..1..1..0....1..1..0..0 %K A224154 nonn %O A224154 1,1 %A A224154 _R. H. Hardin_ Mar 31 2013