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Number of ways to reciprocally link elements of an 6Xn array either to themselves or to exactly two horizontal, diagonal or antidiagonal neighbors
1

%I #4 Dec 18 2012 09:48:16

%S 1,32,2275,331589,42378036,5717794568,759141297226,101519188093819,

%T 13544010607777037,1808631116741400544,241439736338645879892,

%U 32234631644593961566460,4303448709056159145198981

%N Number of ways to reciprocally link elements of an 6Xn array either to themselves or to exactly two horizontal, diagonal or antidiagonal neighbors

%C Row 6 of A220725

%H R. H. Hardin, <a href="/A220730/b220730.txt">Table of n, a(n) for n = 1..41</a>

%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 .69.46.47...69.47.00...00.79.00...00.00.00...00.67.47...00.79.00...00.00.00

%e .00.13.00...36.14.00...36.47.17...00.67.47...39.37.00...39.67.14...69.46.47

%e .00.67.47...00.79.00...39.37.00...39.37.00...36.14.00...36.14.00...00.13.00

%e .39.39.00...39.00.17...39.19.00...39.17.00...00.69.47...00.00.00...69.46.47

%e .00.16.14...00.13.00...00.16.14...39.16.47...00.39.17...00.00.00...00.13.00

%e .00.00.00...00.00.00...00.00.00...00.13.00...00.36.14...00.00.00...00.00.00

%K nonn

%O 1,2

%A _R. H. Hardin_ Dec 18 2012