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A223831 T(n,k)=Number of nXk 0..2 arrays with rows and columns unimodal.

%I A223831 #6 Jul 23 2025 04:34:56
%S A223831 3,9,9,22,81,22,46,484,484,46,86,2116,6166,2116,86,148,7396,51136,
%T A223831 51136,7396,148,239,21904,310396,738482,310396,21904,239,367,57121,
%U A223831 1492552,7291180,7291180,1492552,57121,367,541,134689,5995781,54035194,111026387
%N A223831 T(n,k)=Number of nXk 0..2 arrays with rows and columns unimodal.
%C A223831 Table starts
%C A223831 ...3......9........22..........46............86.............148
%C A223831 ...9.....81.......484........2116..........7396...........21904
%C A223831 ..22....484......6166.......51136........310396.........1492552
%C A223831 ..46...2116.....51136......738482.......7291180........54035194
%C A223831 ..86...7396....310396.....7291180.....111026387......1215505987
%C A223831 .148..21904...1492552....54035194....1215505987.....18986502099
%C A223831 .239..57121...5995781...320423509...10278415020....222531132820
%C A223831 .367.134689..20879061..1590193515...70637615542...2068398813560
%C A223831 .541.292681..64727664..6823643014..409495177832..15880238812350
%C A223831 .771.594441.182215264.25942390362.2059270878998.103853282918692
%H A223831 R. H. Hardin, <a href="/A223831/b223831.txt">Table of n, a(n) for n = 1..144</a>
%F A223831 Empirical: columns k=1..7 are polynomials of degree 4*k
%e A223831 Some solutions for n=3 k=4
%e A223831 ..1..2..0..0....0..0..1..1....0..2..2..0....1..2..1..0....0..1..1..1
%e A223831 ..2..2..0..0....1..2..1..1....0..2..2..2....0..2..1..1....1..1..2..2
%e A223831 ..0..2..1..0....0..0..1..1....0..0..2..2....0..1..2..2....0..1..2..1
%Y A223831 Column 1 is A223718
%Y A223831 Column 2 is A223719
%K A223831 nonn,tabl
%O A223831 1,1
%A A223831 _R. H. Hardin_ Mar 27 2013