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%I #5 Mar 31 2012 12:37:29
%S 1,2,16,72,243,1125,5000,20480,86528,371293,1565109,6612354,28063056,
%T 118894600,503284375,2132531225,9034882704,38268370944,162106085376,
%U 686719856393,2908947562937,12322398111010,52198820570000
%N Number of nX3 array permutations with every element making zero or one right-handed knight moves (out 2, right 1)
%C Column 3 of A209543
%H R. H. Hardin, <a href="/A209538/b209538.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) +a(n-2) -72*a(n-5) +288*a(n-6) +72*a(n-7) +306*a(n-10) -1224*a(n-11) -306*a(n-12) +72*a(n-15) -288*a(n-16) -72*a(n-17) -a(n-20) +4*a(n-21) +a(n-22)
%e Some solutions for n=4
%e ..0..1..7....0..1..7....0..1..2....0..1..2....0..1..7....0..6..7....5..6..2
%e ..8..4..5....3..4.10....8..4.10....3..9.10....8..9..5....3..4.10....8..4..0
%e .11..2..3...11..2..8...11..7..3...11..7..8...11..2..3....1..2..8....1..7..3
%e ..9.10..6....9..5..6....9..5..6....4..5..6....4.10..6....9..5.11....9.10.11
%K nonn
%O 1,2
%A _R. H. Hardin_ Mar 10 2012
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