A220730 - OEIS

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A220730

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

1, 32, 2275, 331589, 42378036, 5717794568, 759141297226, 101519188093819, 13544010607777037, 1808631116741400544, 241439736338645879892, 32234631644593961566460, 4303448709056159145198981

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

COMMENTS

Row 6 of A220725

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..41

EXAMPLE

Some solutions for n=3 0=self 1=nw 3=ne 4=w 6=e 7=sw 9=se (reciprocal directions total 10)

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

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

.00.67.47...00.79.00...39.37.00...39.37.00...36.14.00...36.14.00...00.13.00