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%I #5 Mar 31 2012 12:36:58
%S 888,4737,20290,72777,230014,656441,1728140,4246268,9847415,21700159,
%T 45744109,92663818,181178545,343044939,630954514,1130114352,
%U 1975727787,3377874220,5657695118,9297612083,15012132902,23843994305,37296211132
%N Number of (n+1)X5 0..2 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 4 of A203728
%H R. H. Hardin, <a href="/A203724/b203724.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 9*a(n-1) -30*a(n-2) +30*a(n-3) +75*a(n-4) -243*a(n-5) +152*a(n-6) +360*a(n-7) -690*a(n-8) +130*a(n-9) +780*a(n-10) -780*a(n-11) -130*a(n-12) +690*a(n-13) -360*a(n-14) -152*a(n-15) +243*a(n-16) -75*a(n-17) -30*a(n-18) +30*a(n-19) -9*a(n-20) +a(n-21) for n>26
%e Some solutions for n=4
%e ..1..2..2..2..2....1..1..1..2..1....1..2..2..2..2....0..1..1..1..0
%e ..1..2..2..2..2....1..1..2..1..2....1..2..2..2..2....2..1..1..1..2
%e ..1..2..2..2..2....0..2..1..2..1....1..2..2..2..2....1..2..2..2..2
%e ..2..2..2..2..2....1..1..2..1..2....1..2..2..2..2....1..2..2..2..2
%e ..2..2..2..2..2....0..2..1..2..1....1..2..2..2..2....2..2..2..2..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 05 2012
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