A220732 - OEIS

A220732

Number of ways to reciprocally link elements of an n X n array either to themselves or to exactly two horizontal, diagonal and antidiagonal neighbors, without consecutive collinear links

%I #5 Dec 18 2015 18:18:24

%S 1,2,22,712,127288,94226589,319803318494,4830469921091502,

%T 326643330141438534391

%N Number of ways to reciprocally link elements of an n X n array either to themselves or to exactly two horizontal, diagonal and antidiagonal neighbors, without consecutive collinear links

%C Diagonal 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 .00.67.47...00.69.47...00.69.47...00.69.47...00.67.47...00.00.00...00.79.00

%e .36.34.00...69.34.17...00.39.17...00.36.14...39.39.00...00.67.47...39.67.14

%e .00.00.00...00.13.00...00.36.14...00.00.00...00.16.14...36.34.00...36.14.00

%K nonn

%O 1,2

%A _R. H. Hardin_ Dec 18 2012