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A223790 Number of 3Xn 0..2 arrays with rows, diagonals and antidiagonals unimodal 1

%I

%S 27,729,8635,62365,334230,1455816,5425943,17876443,53233499,145612231,

%T 370377451,884526855,1998822498,4301425736,8862298953,17560558967,

%U 33594162385,62253768525,112071502931,196491932081,336258321854

%N Number of 3Xn 0..2 arrays with rows, diagonals and antidiagonals unimodal

%C Row 3 of A223789

%H R. H. Hardin, <a href="/A223790/b223790.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = (5051/239500800)*n^12 + (9539/39916800)*n^11 + (86021/21772800)*n^10 + (2861/103680)*n^9 + (1419461/7257600)*n^8 + (453883/403200)*n^7 + (30663023/21772800)*n^6 + (10887469/725760)*n^5 - (167107181/5443200)*n^4 + (16805993/129600)*n^3 - (226950043/831600)*n^2 + (1171756/3465)*n - 185 for n>1

%e Some solutions for n=3

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 27 2013

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Last modified May 20 15:14 EDT 2022. Contains 353874 sequences. (Running on oeis4.)