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%I #7 Aug 12 2016 06:53:58
%S 1,2,56,184740,137409486772,36724170744914466520,
%T 5395269899168064415277849230476
%N Number of n X n arrays containing n copies of 0..n-1 with no equal horizontal neighbors and new values introduced sequentially from 0.
%C Diagonal of A264945.
%e Some solutions for n=4
%e ..0..1..2..0....0..1..2..0....0..1..0..1....0..1..2..0....0..1..0..2
%e ..3..2..0..3....0..2..3..1....2..1..3..0....3..2..1..2....2..1..2..3
%e ..3..2..1..3....1..2..1..3....2..3..2..3....0..3..0..1....0..1..0..3
%e ..0..1..2..1....2..3..0..3....2..3..0..1....3..1..3..2....2..3..1..3
%Y Cf. A264945.
%K nonn
%O 1,2
%A _R. H. Hardin_, Nov 29 2015