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%I #4 Jan 11 2015 09:58:51
%S 1998,10182,77414,382973,1636717,5648005,17980643,52078415,140931619,
%T 357840627,868453186,2023764359,4558420081,9965846712,21261754665,
%U 44410393873,91091870910,183925891758,366444204565,721742419593
%N Number of (n+1)X(3+1) 0..2 arrays with every 2X2 subblock ne-sw antidiagonal difference nondecreasing horizontally and nw+se diagonal sum nondecreasing vertically
%C Column 3 of A253749
%H R. H. Hardin, <a href="/A253744/b253744.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 7*a(n-1) -19*a(n-2) +24*a(n-3) -6*a(n-4) -41*a(n-5) +105*a(n-6) -121*a(n-7) +34*a(n-8) +108*a(n-9) -232*a(n-10) +235*a(n-11) -48*a(n-12) -163*a(n-13) +253*a(n-14) -209*a(n-15) +10*a(n-16) +148*a(n-17) -130*a(n-18) +67*a(n-19) +26*a(n-20) -79*a(n-21) +19*a(n-22) +13*a(n-23) -14*a(n-24) +24*a(n-25) -7*a(n-27) -4*a(n-28) -5*a(n-29) +7*a(n-30) -3*a(n-31) +3*a(n-32) +a(n-33) -3*a(n-34) +a(n-35) for n>45
%e Some solutions for n=3
%e ..1..1..0..1....1..2..1..2....1..0..0..2....1..0..0..2....1..0..0..1
%e ..1..0..0..2....2..0..0..1....1..0..1..1....0..0..1..1....1..0..0..0
%e ..1..1..1..2....2..1..2..2....2..1..1..2....2..1..1..2....2..1..0..0
%e ..1..1..1..1....2..2..1..2....2..0..1..2....1..1..0..2....2..1..1..2
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 11 2015
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