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Number of 5Xn 0..1 arrays with rows and antidiagonals unimodal and columns nondecreasing
1

%I #4 Mar 27 2013 17:22:03

%S 6,36,149,471,1240,2884,6159,12371,23716,43790,78342,136368,231677,

%T 385101,627571,1004341,1580713,2449699,3742152,5640008,8393406,

%U 12342594,17945687,25813519,36753026,51820812,72388786,100224016,137585227

%N Number of 5Xn 0..1 arrays with rows and antidiagonals unimodal and columns nondecreasing

%C Row 5 of A223838

%H R. H. Hardin, <a href="/A223841/b223841.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = (1/3628800)*n^10 - (1/241920)*n^9 + (17/120960)*n^8 - (1/13440)*n^7 + (3733/172800)*n^6 - (893/11520)*n^5 + (178931/90720)*n^4 - (188123/60480)*n^3 + (504149/25200)*n^2 - (30581/420)*n + 121 for n>4

%e Some solutions for n=3

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 27 2013