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%I #5 Aug 12 2016 07:04:21
%S 0,2,24,792,39360,2396880,241012800,27159592320,4466274785280,
%T 806760393465600,197138895617664000,52164067053271219200
%N Number of nX2 arrays containing 2 copies of 0..n-1 with no element plus any horizontal neighbor equal to n-1.
%C Column 2 of A265882.
%e Some solutions for n=4
%e ..2..3....2..2....2..0....0..0....0..1....2..0....0..1....0..0....2..3....0..1
%e ..1..3....3..3....1..3....2..3....1..0....0..1....3..2....1..3....1..0....0..2
%e ..0..2....0..0....1..0....1..1....2..3....3..2....0..1....3..1....1..3....3..2
%e ..1..0....1..1....3..2....3..2....2..3....1..3....2..3....2..2....2..0....1..3
%Y Cf. A265882.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 17 2015