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A250996 Number of (2+1)X(n+1) 0..2 arrays with nondecreasing min(x(i,j),x(i,j-1)) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction 1

%I

%S 158,872,4007,16993,67409,255502,934786,3328627,11598747,39713993,

%T 134023188,446828435,1474417169,4822285168,15651307633,50458460322,

%U 161715555989,515580776806,1636125457220,5170388337278,16277908434300

%N Number of (2+1)X(n+1) 0..2 arrays with nondecreasing min(x(i,j),x(i,j-1)) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction

%C Row 2 of A250994

%H R. H. Hardin, <a href="/A250996/b250996.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 9*a(n-1) -23*a(n-2) -12*a(n-3) +120*a(n-4) -72*a(n-5) -213*a(n-6) +197*a(n-7) +179*a(n-8) -186*a(n-9) -81*a(n-10) +75*a(n-11) +22*a(n-12) -11*a(n-13) -3*a(n-14)

%e Some solutions for n=4

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 29 2014

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Last modified April 11 16:42 EDT 2021. Contains 342888 sequences. (Running on oeis4.)