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Number of 3Xn 0..2 arrays with rows and antidiagonals unimodal and columns nondecreasing
1

%I #4 Apr 02 2013 06:54:04

%S 10,100,648,3096,12032,40182,119367,322885,808618,1898050,4215105,

%T 8921265,18101023,35375831,66857059,122591129,218705294,380533212,

%U 647088610,1077366434,1759087854,2820672704,4447425227,6903161705

%N Number of 3Xn 0..2 arrays with rows and antidiagonals unimodal and columns nondecreasing

%C Row 3 of A224262

%H R. H. Hardin, <a href="/A224263/b224263.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = (1/19160064)*n^12 + (1/1064448)*n^11 + (181/6220800)*n^10 + (557/1451520)*n^9 + (13571/2903040)*n^8 + (3197/96768)*n^7 + (8451841/43545600)*n^6 + (316789/483840)*n^5 + (535159/311040)*n^4 + (151169/72576)*n^3 + (9281749/1663200)*n^2 - (73057/13860)*n + 5

%e Some solutions for n=3

%e ..0..0..1....0..1..0....1..2..1....0..0..2....0..0..0....1..1..0....0..0..0

%e ..2..2..1....1..2..0....2..2..2....0..1..2....0..1..0....2..1..0....0..1..0

%e ..2..2..1....2..2..0....2..2..2....1..2..2....0..1..0....2..2..1....2..1..1

%K nonn

%O 1,1

%A _R. H. Hardin_ Apr 02 2013