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%I #4 Mar 28 2013 10:20:06
%S 64,4096,99223,1336985,12520369,90648289,539511985,2744980059,
%T 12266400036,49108723398,178849231722,599732197006,1869990523340,
%U 5465951755716,15079975128525,39496585750239,98695673406660
%N Number of 3Xn 0..3 arrays with rows, diagonals and antidiagonals unimodal
%C Row 3 of A223876
%H R. H. Hardin, <a href="/A223877/b223877.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = (89/169374965760)*n^18 + (838301/44460928512000)*n^17 + (1621091/3487131648000)*n^16 + (1400869/186810624000)*n^15 + (17909/188697600)*n^14 + (173367409/186810624000)*n^13 + (137278391/19160064000)*n^12 + (407205871/8382528000)*n^11 + (181325017/812851200)*n^10 + (3123945389/2612736000)*n^9 + (24186912011/12773376000)*n^8 + (223345835639/14370048000)*n^7 - (117158072963/4151347200)*n^6 + (56268858807829/326918592000)*n^5 - (9869157660331/19813248000)*n^4 + (26939359241/20270250)*n^3 - (1768948870159/735134400)*n^2 + (1057606733/408408)*n - 1275 for n>1
%e Some solutions for n=3
%e ..3..2..0....0..1..1....3..1..0....0..1..0....1..1..2....3..2..1....1..2..1
%e ..3..3..1....3..3..3....1..1..0....2..3..1....1..2..2....2..3..1....2..2..1
%e ..2..2..3....1..2..1....1..3..1....0..2..3....0..1..0....3..2..2....0..0..3
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 28 2013
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