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%I #7 Jul 26 2018 11:54:53
%S 3,11,27,56,105,183,301,472,711,1035,1463,2016,2717,3591,4665,5968,
%T 7531,9387,11571,14120,17073,20471,24357,28776,33775,39403,45711,
%U 52752,60581,69255,78833,89376,100947,113611,127435,142488,158841,176567,195741
%N Number of n X 2 arrays of the minimum value of corresponding elements and their horizontal or antidiagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and columns, 0..2 n X 2 array.
%C Column 2 of A219627.
%H R. H. Hardin, <a href="/A219621/b219621.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = (1/12)*n^4 + (23/12)*n^2 + n.
%F Conjectures from _Colin Barker_, Jul 26 2018: (Start)
%F G.f.: x*(3 - 4*x + 2*x^2 + x^3) / (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>5.
%F (End)
%e Some solutions for n=3:
%e ..0..0....0..0....0..0....1..1....0..0....0..0....0..0....1..1....0..0....0..0
%e ..0..1....0..0....0..1....0..0....1..1....0..0....0..0....1..1....0..1....0..0
%e ..1..2....2..2....1..1....0..2....1..1....0..2....1..1....1..2....0..0....1..2
%Y Cf. A219627.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 24 2012
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