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%I #5 Jan 11 2014 11:34:44
%S 256,2982,33640,343500,3415268,32611962,306033109,2817787860,
%T 25672159052,231626605740,2076931776520,18526379447880,
%U 164667929387896,1459450648692460,12908951676356545,114001890051039912
%N Number of (n+1)X(1+1) 0..3 arrays with the sum of each 2X2 subblock maximum and minimum lexicographically nondecreasing rowwise and columnwise
%C Column 1 of A235506
%H R. H. Hardin, <a href="/A235502/b235502.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 16*a(n-1) -996*a(n-3) +2120*a(n-4) +25116*a(n-5) -57572*a(n-6) -356724*a(n-7) +603662*a(n-8) +3113580*a(n-9) -2452580*a(n-10) -15915180*a(n-11) -310416*a(n-12) +41666900*a(n-13) +22553332*a(n-14) -51946236*a(n-15) -50892645*a(n-16) +22355988*a(n-17) +43357140*a(n-18) +7658496*a(n-19) -11766240*a(n-20) -6600960*a(n-21) -1036800*a(n-22)
%e Some solutions for n=3
%e ..1..1....1..2....1..2....0..3....2..2....2..0....2..1....2..3....0..1....3..0
%e ..0..0....0..2....1..0....0..3....2..0....2..1....3..1....0..1....0..3....0..3
%e ..2..3....2..1....0..3....2..3....0..2....2..3....3..3....3..3....0..2....3..0
%e ..3..1....3..2....1..2....0..2....3..2....2..3....2..3....3..0....3..1....3..3
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 11 2014
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