%I #5 Mar 15 2023 14:09:39
%S 1,64,3403,355883,32924133,3287610473,319803318494,31411054258761,
%T 3063698245151388
%N Number of ways to reciprocally link elements of an 7 X n array either to themselves or to exactly two horizontal, diagonal and antidiagonal neighbors, without consecutive collinear links.
%C Row 7 of A220738.
%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 .00.00.00...00.79.00...00.69.47...00.67.47...00.00.00...69.49.00...00.67.47
%e .00.00.00...39.69.14...00.36.14...39.39.00...00.67.47...00.17.17...36.34.00
%e .00.79.00...00.16.14...00.69.47...00.17.17...36.34.00...36.34.00...00.00.00
%e .39.79.17...69.47.00...00.36.14...36.34.00...69.49.00...69.47.00...00.69.47
%e .39.13.17...36.14.00...00.79.00...69.47.00...69.14.17...36.14.00...00.36.14
%e .00.13.00...69.47.00...39.69.14...39.17.00...00.13.00...69.47.00...00.00.00
%e .00.00.00...36.14.00...00.16.14...36.14.00...00.00.00...36.14.00...00.00.00
%Y Cf. A220738.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 18 2012
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