A223976 - OEIS

%I #4 Mar 30 2013 07:34:20

%S 27,729,9515,76092,440628,2026448,7829639,26375691,79507149,218578373,

%T 555979549,1323191288,2972776392,6350443334,12975277251,25482263325,

%U 48302292951,88682057873,158180868607,274824912452,466153399196

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

%C Row 3 of A223975

%H R. H. Hardin, <a href="/A223976/b223976.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = (5051/239500800)*n^12 + (17911/39916800)*n^11 + (132833/21772800)*n^10 + (35869/725760)*n^9 + (2045741/7257600)*n^8 + (425867/403200)*n^7 + (62493899/21772800)*n^6 + (727483/145152)*n^5 + (33993559/5443200)*n^4 + (2107249/907200)*n^3 + (3822521/831600)*n^2 + (49331/13860)*n + 1

%e Some solutions for n=3

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 30 2013