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Number of nX2 array permutations with each element moved no more than a city block distance of two
1

%I #5 Mar 31 2012 12:36:14

%S 2,24,362,3969,45288,532224,6187928,71851073,835579642,9715691800,

%T 112952196626,1313218423169,15268015911568,177510903321088,

%U 2063800528041456,23994446285179649,278967524405993266

%N Number of nX2 array permutations with each element moved no more than a city block distance of two

%C Column 2 of A188958

%H R. H. Hardin, <a href="/A188953/b188953.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n) = 10*a(n-1) +7*a(n-2) +156*a(n-3) -169*a(n-4) -410*a(n-5) -17*a(n-6) +576*a(n-7) -271*a(n-8) +310*a(n-9) -119*a(n-10) +68*a(n-11) -7*a(n-12) -6*a(n-13) +a(n-14)

%e Some solutions for 3X2

%e ..3..2....1..0....1..2....3..2....1..2....3..1....4..0....1..5....0..1....1..5

%e ..1..0....3..4....0..4....4..0....0..3....2..0....3..2....4..0....4..2....3..4

%e ..4..5....2..5....3..5....5..1....5..4....4..5....5..1....2..3....3..5....0..2

%K nonn

%O 1,1

%A _R. H. Hardin_ Apr 14 2011