A220731 - OEIS

A220731

Number of ways to reciprocally link elements of an 7Xn array either to themselves or to exactly two horizontal, diagonal or antidiagonal neighbors

1, 64, 9667, 3751888, 1208447287, 418227762771, 141539684300104, 48392485908572308

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

OFFSET

1,2

COMMENTS

Row 7 of A220725

LINKS

EXAMPLE

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

.69.47.00...00.00.00...69.49.00...00.67.47...69.49.00...00.69.47...00.00.00

.36.14.00...00.79.00...00.16.14...39.36.47...00.17.17...69.34.17...00.79.00

.69.47.00...36.46.14...69.46.47...00.13.00...36.34.00...00.13.00...36.49.17

.39.17.00...00.00.00...00.13.00...00.00.00...69.49.00...00.67.47...00.36.14

.36.14.00...00.00.00...00.79.00...00.79.00...00.17.17...39.37.00...00.79.00

.00.67.47...69.49.00...39.67.14...36.46.14...39.37.00...39.19.00...39.67.14

.36.34.00...00.16.14...36.14.00...00.00.00...36.14.00...00.16.14...36.14.00

CROSSREFS

KEYWORD

nonn

AUTHOR

STATUS

approved