A209391 - OEIS

%I #5 Mar 31 2012 12:37:28

%S 1,2,16,152,1449,11655,89469,705803,5771383,45213223,344221421,

%T 2576621623,19476715122,147713174987,1110131277687,8315461638940,

%U 62491630903612,470960349189386,3550021202822759,26747955424745122

%N Number of nX2 1..4 arrays with every element value z a city block distance of exactly z from another element value z

%C Column 2 of A209394

%H R. H. Hardin, <a href="/A209391/b209391.txt">Table of n, a(n) for n = 1..122</a>

%e Some solutions for n=7

%e ..1..4....3..4....3..3....2..3....3..2....4..3....2..3....4..2....1..4....4..1

%e ..1..1....2..2....4..4....2..4....2..1....2..3....1..1....2..3....1..4....4..1

%e ..4..2....2..2....1..3....2..2....2..1....3..2....2..2....3..1....1..4....3..1

%e ..4..4....3..2....1..3....3..3....3..3....3..4....3..3....2..1....4..4....4..4

%e ..1..2....2..4....4..4....4..2....2..1....3..1....2..2....4..3....1..1....4..3

%e ..1..1....2..3....1..3....2..4....3..1....1..1....1..1....3..1....1..4....4..2

%e ..4..4....3..2....1..3....3..3....2..3....1..3....3..2....1..1....4..4....2..4

%K nonn

%O 1,2

%A _R. H. Hardin_ Mar 07 2012