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%I #7 Mar 16 2018 07:30:11
%S 8,64,292,948,2527,5913,12577,24821,46068,81198,136930,222250,348885,
%T 531823,789879,1146307,1629458,2273484,3119088,4214320,5615419,
%U 7387701,9606493,12358113,15740896,19866266,24859854,30862662,38032273,46544107
%N Number of 3 X n 0..1 arrays with rows, diagonals and antidiagonals unimodal.
%C Row 3 of A223669.
%H R. H. Hardin, <a href="/A223670/b223670.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = (23/360)*n^6 - (3/40)*n^5 + (37/18)*n^4 + (119/24)*n^3 - (3103/360)*n^2 + (997/60)*n - 9 for n>1.
%F Conjectures from _Colin Barker_, Mar 16 2018: (Start)
%F G.f.: x*(8 + 8*x + 12*x^2 - 32*x^3 + 63*x^4 - 16*x^5 + 5*x^6 - 2*x^7) / (1 - x)^7.
%F a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7) for n>8.
%F (End)
%e Some solutions for n=4:
%e ..0..1..1..1....0..1..1..0....0..0..1..1....0..0..0..1....1..0..0..0
%e ..1..1..0..0....0..1..0..0....0..1..0..0....0..0..1..1....0..1..1..1
%e ..0..0..0..0....0..1..1..0....1..0..0..0....0..1..1..0....0..0..0..0
%Y Cf. A223669.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 25 2013
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