%I #7 Mar 31 2012 12:36:58
%S 90,499,2166,8667,31942,111916,376415,1228141,3911718,12225055,
%T 37629475,114415963,344453875,1028640925,3051602949,9004181108,
%U 26450597561,77418965194,225924263865,657679624225,1910701827288,5541861127364
%N Number of (n+1)X2 0..3 arrays with column and row pair sums b(i,j)=a(i,j)+a(i,j-1) and c(i,j)=a(i,j)+a(i-1,j) nondecreasing in column and row directions, respectively
%C Column 1 of A203741
%F Empirical: a(n) = 10*a(n-1) -35*a(n-2) +35*a(n-3) +72*a(n-4) -178*a(n-5) +7*a(n-6) +259*a(n-7) -123*a(n-8) -182*a(n-9) +125*a(n-10) +68*a(n-11) -56*a(n-12) -13*a(n-13) +12*a(n-14) +a(n-15) -a(n-16)
%e Some solutions for n=4
%e ..0..3....2..2....0..1....0..2....2..0....1..3....3..3....0..1....1..0....2..0
%e ..0..3....1..3....0..1....1..3....0..2....1..3....3..3....3..2....0..1....0..2
%e ..1..2....1..3....1..1....2..2....1..2....3..1....3..3....2..3....0..3....1..1
%e ..1..3....2..2....3..3....1..3....3..2....1..3....3..3....3..2....1..2....3..3
%e ..3..3....1..3....3..3....2..2....2..3....1..3....3..3....2..3....1..2....3..3
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 05 2012
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