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Number of 6Xn 0..1 arrays with diagonals and rows unimodal and antidiagonals nondecreasing
1

%I #4 Mar 31 2013 14:45:53

%S 64,972,2935,5657,10562,20065,39037,76393,148637,284937,535211,981957,

%T 1757541,3068802,5231637,8719051,14227266,22765909,35780116,55314683,

%U 84233265,126509183,187608775,274993564,398773975,572555093,814524213

%N Number of 6Xn 0..1 arrays with diagonals and rows unimodal and antidiagonals nondecreasing

%C Row 6 of A224158

%H R. H. Hardin, <a href="/A224162/b224162.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = (1/479001600)*n^12 - (1/15966720)*n^11 + (127/43545600)*n^10 - (7/207360)*n^9 + (4033/2073600)*n^8 - (5443/483840)*n^7 + (13552621/43545600)*n^6 - (8448991/1451520)*n^5 + (1032695879/10886400)*n^4 - (8305531/10368)*n^3 + (67691137/14850)*n^2 - (80407927/5544)*n + 24225 for n>8

%e Some solutions for n=3

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 31 2013