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 A224201 #6 Jul 23 2025 05:02:50 %S A224201 296,17723,586343,16355242,451319098,12652618110,357890479324, %T A224201 10153767871028,288290902851198,8186391229197618,232464667737624940, %U A224201 6601126525130276106,187446397143433832288,5322740642815551322518 %N A224201 Number of nX5 0..3 arrays with rows unimodal and antidiagonals nondecreasing. %C A224201 Column 5 of A224204 %H A224201 R. H. Hardin, <a href="/A224201/b224201.txt">Table of n, a(n) for n = 1..210</a> %F A224201 Empirical: a(n) = 56*a(n-1) -1098*a(n-2) +10776*a(n-3) -59038*a(n-4) +197135*a(n-5) -527776*a(n-6) +1780117*a(n-7) -5020078*a(n-8) +3603978*a(n-9) -19091082*a(n-10) +61460622*a(n-11) +49090018*a(n-12) +274177128*a(n-13) +105163104*a(n-14) +354022404*a(n-15) +28705280*a(n-16) +147891456*a(n-17) -1275168*a(n-18) +15980544*a(n-19) for n>23 %e A224201 Some solutions for n=3 %e A224201 ..0..0..0..1..1....1..0..0..0..0....0..0..0..1..3....1..1..2..1..0 %e A224201 ..0..0..1..3..0....0..0..0..3..1....0..0..3..3..1....2..2..2..1..1 %e A224201 ..2..3..3..2..1....1..2..3..3..0....2..3..3..2..0....2..2..3..3..0 %K A224201 nonn %O A224201 1,1 %A A224201 _R. H. Hardin_ Apr 01 2013