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%I #4 Apr 03 2013 11:04:48
%S 27,324,1586,5996,20214,61953,174378,454832,1108958,2547780,5554847,
%T 11564081,23107746,44519456,83011127,150287312,264917825,455762696,
%U 766835415,1264104630,2044874898,3250558135,5083853932,7831604260
%N Number of 3Xn 0..2 arrays with diagonals and rows unimodal and antidiagonals nondecreasing
%C Row 3 of A224310
%H R. H. Hardin, <a href="/A224311/b224311.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = (1/19160064)*n^12 + (1/1064448)*n^11 + (1507/43545600)*n^10 + (73/161280)*n^9 + (23603/2903040)*n^8 + (111/3584)*n^7 + (13023121/43545600)*n^6 + (130093/96768)*n^5 + (5619469/2177280)*n^4 + (54895/2688)*n^3 - (11456441/1663200)*n^2 + (205131/1540)*n - 196 for n>3
%e Some solutions for n=3
%e ..1..2..0....2..1..1....0..0..0....0..2..1....1..0..0....2..2..1....2..0..0
%e ..2..2..0....2..2..0....0..2..0....2..2..0....0..2..1....2..2..0....0..2..0
%e ..2..2..2....2..0..0....2..0..0....2..1..1....2..2..1....2..2..0....2..1..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Apr 03 2013