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%I #4 Dec 17 2012 04:42:33
%S 1,228,4657,243119,8608738,356768525,13864972277,553125347136,
%T 21831846871613,865461975018339,34247958158855874,1356237159188241529,
%U 53691862459540232153,2125854494007156918632,84166119627538600335289
%N Number of ways to reciprocally link elements of an 5Xn array either to themselves or to exactly one horizontal, diagonal and antidiagonal neighbor
%C Row 5 of A220621
%H R. H. Hardin, <a href="/A220624/b220624.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 29*a(n-1) +557*a(n-2) -4948*a(n-3) -24662*a(n-4) +187560*a(n-5) +182180*a(n-6) -1893504*a(n-7) -127344*a(n-8) +6325072*a(n-9) +132352*a(n-10) -7384448*a(n-11) -1323456*a(n-12) +2439808*a(n-13) +987648*a(n-14) -7168*a(n-15) -69632*a(n-16) +32768*a(n-17)
%e Some solutions for n=3 0=self 1=nw 3=ne 4=w 6=e 7=sw 9=se (reciprocal directions total 10)
%e ..9..0..0....0..7..0....6..4..0....0..7..0....0..6..4....0..0..7....0..6..4
%e ..0..1..0....3..7..0....0..0..0....3..7..0....0..9..0....0..3..0....0..7..0
%e ..6..4..7....3..6..4....0..6..4....3..6..4....0..0..1....0..9..0....3..7..0
%e ..9..3..0....0..7..7....0..6..4....6..4..0....6..4..0....6..4..1....3..0..0
%e ..0..1..0....3..3..0....0..6..4....6..4..0....0..0..0....0..6..4....6..4..0
%K nonn
%O 1,2
%A _R. H. Hardin_ Dec 17 2012
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