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%I #9 Aug 27 2018 06:19:26
%S 16,81,208,419,760,1279,2032,3083,4504,6375,8784,11827,15608,20239,
%T 25840,32539,40472,49783,60624,73155,87544,103967,122608,143659,
%U 167320,193799,223312,256083,292344,332335,376304,424507,477208,534679,597200,665059
%N Number of 4 X n 0..1 arrays with rows nondecreasing and antidiagonals unimodal.
%C Row 4 of A224133.
%H R. H. Hardin, <a href="/A224135/b224135.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = (1/3)*n^4 + 2*n^3 + (26/3)*n^2 + 18*n - 5 for n>2.
%F Conjectures from _Colin Barker_, Aug 27 2018: (Start)
%F G.f.: x*(16 + x - 37*x^2 + 29*x^3 + 15*x^4 - 22*x^5 + 6*x^6) / (1 - x)^5.
%F a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>7.
%F (End)
%e Some solutions for n=3:
%e ..1..1..1....1..1..1....1..1..1....0..0..1....1..1..1....0..0..0....0..1..1
%e ..0..0..1....0..0..0....0..0..0....0..0..0....0..0..1....0..0..0....0..0..1
%e ..0..0..0....0..1..1....0..0..0....0..0..1....0..0..0....1..1..1....0..0..1
%e ..0..0..1....1..1..1....0..1..1....0..0..1....0..1..1....0..0..0....0..1..1
%Y Cf. A224133.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 31 2013