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%I #5 Mar 20 2013 04:32:23
%S 36,1296,11254,449810,13266784,417523315,14781272688,521262156765,
%T 17822960179390,683066414115964,23438466168324477
%N Number of nX3 0..3 arrays with all rows and columns having a nonnegative second derivative in a quadratic least squares fit, with one and two element arrays taken as having a zero second derivative
%C Column 3 of A223406
%e Some solutions for n=3
%e ..3..1..0....2..2..2....1..1..2....1..0..2....1..0..1....3..3..3....3..2..2
%e ..1..0..0....1..1..1....2..1..2....1..0..2....0..0..0....1..0..2....2..0..1
%e ..3..2..1....0..1..2....3..1..3....3..0..2....1..2..3....3..1..3....3..2..3
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 20 2013
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