%I #5 Mar 31 2012 12:37:34
%S 15,176,1533,8824,40038,167910,710895,3139374,14621105,73775740,
%T 381369393,1896558198,8898865547,40479815828,186751218361,
%U 891575695494,4361545055817,21344723416559,102849312863141,487830504402191
%N Number of nX2 1..4 arrays with no element with value z exactly a city block distance of z from another element with value z
%C Column 2 of A210788
%H R. H. Hardin, <a href="/A210782/b210782.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=4
%e ..4..2....3..3....3..4....2..4....1..3....2..1....4..4....4..2....3..1....3..3
%e ..3..3....2..1....4..1....1..3....2..2....2..4....1..2....3..2....2..2....2..1
%e ..1..3....1..4....2..4....3..4....4..3....3..4....3..1....4..4....3..1....4..4
%e ..2..1....4..1....1..3....1..3....1..4....4..2....1..3....4..1....4..3....4..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 26 2012