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%I #5 Mar 31 2012 12:37:29
%S 1,8,243,6480,103680,2080800,42166080,833285376,16312907520,
%T 325995321600,6453963360000,127720737849600,2530106562316032,
%U 50139779258799360,992798704350478080,19665530247158611200,389544838379796084480
%N Number of nX5 array permutations with every element making zero or one right-handed knight moves (out 2, right 1)
%C Column 5 of A209543
%H R. H. Hardin, <a href="/A209540/b209540.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 19*a(n-1) +16*a(n-2) -119472*a(n-5) +2269968*a(n-6) +1911552*a(n-7) +606867456*a(n-10) -11530481664*a(n-11) -9709879296*a(n-12) +125275471872*a(n-15) -2380233965568*a(n-16) -2004407549952*a(n-17) -1099511627776*a(n-20) +20890720927744*a(n-21) +17592186044416*a(n-22) for n>24
%e Some solutions for n=4
%e ..7.10..2..3.13....0..8..2..3.13....0.10..2..3.13....0.10.11.12..4
%e ..5.15..0.17..9....5.15.14.17..9....5..6.14.17.18....5..6.14.17..9
%e ..1.18.19..4.14....1.11.19..4..7....1.11.12..4..7....1..2..3.13..7
%e ..6.16..8.11.12....6.16.10.18.12...15.16..8..9.19...15.16..8.18.19
%K nonn
%O 1,2
%A _R. H. Hardin_ Mar 10 2012
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