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Number of (n+1)X(2+1) 0..2 arrays with every 2X2 subblock ne-sw antidiagonal difference nondecreasing horizontally and nw+se diagonal sum nondecreasing vertically
1

%I #4 Jan 11 2015 09:58:12

%S 450,2723,16625,75959,305707,1087364,3598487,11219006,33417573,

%T 95950526,267699183,729912815,1953438640,5149262462,13406957125,

%U 34558018931,88348005194,224349137386,566585100420,1424483824200,3568296361053

%N Number of (n+1)X(2+1) 0..2 arrays with every 2X2 subblock ne-sw antidiagonal difference nondecreasing horizontally and nw+se diagonal sum nondecreasing vertically

%C Column 2 of A253749

%H R. H. Hardin, <a href="/A253743/b253743.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 9*a(n-1) -31*a(n-2) +46*a(n-3) -127*a(n-5) +260*a(n-6) -204*a(n-7) -196*a(n-8) +680*a(n-9) -740*a(n-10) +140*a(n-11) +901*a(n-12) -1486*a(n-13) +887*a(n-14) +429*a(n-15) -1605*a(n-16) +1729*a(n-17) -497*a(n-18) -945*a(n-19) +1656*a(n-20) -1324*a(n-21) +50*a(n-22) +1021*a(n-23) -1199*a(n-24) +685*a(n-25) +209*a(n-26) -744*a(n-27) +594*a(n-28) -176*a(n-29) -215*a(n-30) +343*a(n-31) -171*a(n-32) -14*a(n-33) +94*a(n-34) -87*a(n-35) +21*a(n-36) +19*a(n-37) -18*a(n-38) +9*a(n-39) -3*a(n-41) +a(n-42) for n>46

%e Some solutions for n=4

%e ..0..0..2....1..0..2....1..2..1....2..0..2....1..0..2....0..0..0....1..1..0

%e ..2..0..2....2..0..0....1..0..0....1..0..1....1..0..1....1..1..1....1..0..0

%e ..0..0..2....2..0..1....1..0..2....0..1..2....2..0..1....2..1..1....1..1..2

%e ..2..2..2....2..2..2....1..0..2....1..2..2....2..0..1....2..2..2....2..1..1

%e ..0..0..1....2..2..1....0..0..2....2..2..1....0..0..1....2..2..1....2..1..1

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 11 2015