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%I #6 Dec 28 2023 19:23:06
%S 1,2,16,152,1721,21083,217825,2135214,20752645,208916566,2138876698
%N Number of n X 2 1..5 arrays with every element value z a city block distance of exactly z from another element value z.
%C Column 2 of A209023.
%e Some solutions for n=6
%e ..4..3....4..3....3..1....4..2....3..2....2..2....5..5....2..5....1..4....4..1
%e ..5..4....3..5....3..1....2..3....3..3....4..2....2..1....4..4....1..1....1..1
%e ..3..1....4..2....2..3....3..2....2..2....4..2....3..1....2..1....1..4....1..2
%e ..1..1....2..3....2..3....3..3....3..2....2..2....2..2....1..1....1..2....2..4
%e ..4..2....4..2....2..2....4..3....3..1....2..4....5..3....5..4....1..4....2..2
%e ..2..5....5..4....1..1....3..3....1..1....4..4....5..2....4..4....4..2....2..2
%Y Cf. A209023.
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 04 2012