%I #6 Mar 31 2012 12:37:28
%S 0,1,1,3,3,13,16,42,74,161,303,631,1212,2446,4847,9714,19142,38031,
%T 75367,149813,296961,589537,1169118,2319453,4603741,9137804,18132445,
%U 35982420,71413411,141734249,281295511,558288679,1107995542,2198965721,4364220336
%N Number of nX1 1..4 arrays with every element value z a city block distance of exactly z from another element value z
%C Column 1 of A209394
%H R. H. Hardin, <a href="/A209390/b209390.txt">Table of n, a(n) for n = 1..210</a>
%e All solutions for n=7
%e ..3....4....2....3....3....3....1....1....3....1....4....1....2....1....2....2
%e ..4....2....2....4....3....1....1....1....1....1....1....1....2....1....2....4
%e ..2....4....2....2....3....1....1....2....1....1....1....1....2....4....2....2
%e ..3....2....2....3....3....3....1....2....3....3....1....2....2....1....2....3
%e ..2....4....1....2....3....1....1....2....1....1....4....2....2....1....2....2
%e ..4....2....1....4....3....1....1....2....1....1....1....2....2....1....1....4
%e ..3....4....1....2....3....3....1....2....1....3....1....2....2....4....1....3
%K nonn
%O 1,4
%A _R. H. Hardin_ Mar 07 2012
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