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%I #5 Dec 18 2015 18:18:54
%S 1,6,1376,1211112,4131348480,49965944917500,2284546587678218240,
%T 399352031269643676301056
%N Number of n X n 0..2n-2 arrays with upper left zero and lower right 2n-2 and each element differing from its diagonal and antidiagonal neighbors by one or two.
%C Diagonal of A265480.
%e Some solutions for n=3
%e ..0..2..0....0..3..0....0..2..0....0..4..3....0..2..1....0..2..4....0..1..0
%e ..0..2..0....4..2..2....4..2..3....3..2..3....3..2..3....4..2..4....0..2..0
%e ..3..2..4....4..3..4....0..2..4....0..2..4....0..1..4....0..3..4....3..2..4
%Y Cf. A265480.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 09 2015