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%I #6 Jan 05 2022 23:16:42
%S 233,2322,21753,204721,1920345,18018051,169000988,1585251989,
%T 14869200736,139470660434,1308202626738,12270670938062,
%U 115096226185535,1079578101818582,10126210672951525,94981688990498297,890907882411650813
%N Number of (n+1) X (4+1) 0..1 arrays with nondecreasing min(x(i,j),x(i,j-1)) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction.
%C Column 4 of A250468.
%H R. H. Hardin, <a href="/A250464/b250464.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) +46*a(n-2) -95*a(n-3) -445*a(n-4) +586*a(n-5) +1578*a(n-6) -1665*a(n-7) -2478*a(n-8) +2288*a(n-9) +1812*a(n-10) -1488*a(n-11) -576*a(n-12) +400*a(n-13) +64*a(n-14) -32*a(n-15).
%e Some solutions for n=3
%e ..0..1..0..0..0....0..0..0..0..1....0..0..1..0..1....0..0..0..0..0
%e ..0..0..0..1..0....1..0..0..0..0....0..0..0..0..1....1..0..1..0..1
%e ..1..0..0..0..1....0..0..1..1..1....0..0..0..0..0....0..1..0..0..0
%e ..0..1..1..1..1....1..0..1..1..1....0..1..0..0..1....1..0..1..1..0
%Y Cf. A250468.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 23 2014
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