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%I #8 Sep 27 2015 17:42:22
%S 69,2028,100512,7184212,900035309,198343663311,98349771149487,
%T 65382647775609882,75717898362438396460
%N Number of (n+2)X(n+2) nonnegative integer arrays with all values the knight distance from the upper left minus as much as 3, with successive minimum path knight move differences either 0 or +1, and any unreachable value zero.
%C Diagonal of A253342.
%e Some solutions for n=3
%e ..0..1..1..2..1....0..3..2..2..1....0..1..0..0..1....0..2..2..1..1
%e ..2..3..1..1..1....2..3..1..2..2....1..1..0..0..0....2..2..0..2..2
%e ..1..0..2..2..1....2..1..3..2..2....0..0..1..1..0....1..1..2..2..1
%e ..2..1..2..1..1....2..2..2..1..2....1..0..0..0..1....2..1..2..1..2
%e ..1..1..1..1..2....1..2..1..2..3....0..0..0..1..1....1..1..2..1..2
%e Knight distance matrix for n=3
%e ..0..3..2..3..2
%e ..3..4..1..2..3
%e ..2..1..4..3..2
%e ..3..2..3..2..3
%e ..2..3..2..3..4
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 30 2014