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%I #7 Aug 24 2018 08:52:29
%S 16,81,177,321,558,928,1479,2267,3356,4818,6733,9189,12282,16116,
%T 20803,26463,33224,41222,50601,61513,74118,88584,105087,123811,144948,
%U 168698,195269,224877,257746,294108,334203,378279,426592,479406,536993,599633
%N Number of 4 X n 0..1 arrays with diagonals and antidiagonals unimodal and rows nondecreasing.
%C Row 4 of A223949.
%H R. H. Hardin, <a href="/A223951/b223951.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = (1/3)*n^4 + (2/3)*n^3 + (37/6)*n^2 + (107/6)*n + 23 for n>2.
%F Conjectures from _Colin Barker_, Aug 24 2018: (Start)
%F G.f.: x*(16 + x - 68*x^2 + 86*x^3 - 7*x^4 - 33*x^5 + 13*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 ..0..1..1....1..1..1....0..0..1....0..1..1....0..0..1....0..0..0....0..0..0
%e ..0..0..0....0..1..1....0..0..0....1..1..1....0..0..1....1..1..1....0..1..1
%e ..0..1..1....0..1..1....0..0..0....1..1..1....0..1..1....0..0..0....1..1..1
%e ..0..0..1....0..1..1....0..0..1....1..1..1....0..0..1....0..0..0....0..0..1
%Y Cf. A223949.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 29 2013
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