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A220743 Number of ways to reciprocally link elements of an 6 X n array either to themselves or to exactly two horizontal, diagonal and antidiagonal neighbors, without consecutive collinear links. 1
1, 32, 949, 45421, 2027456, 94226589, 4335687696, 201959426140, 9355392933041, 434476062233061, 20160870899222101, 935844654794161538, 43434200828618562852, 2016001500367387183289, 93570090322331503458132 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row 6 of A220738.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..50

EXAMPLE

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

.69.49.00...00.00.00...00.67.47...00.67.47...00.00.00...69.49.00...00.79.00

.69.14.17...69.49.00...36.34.00...36.34.00...69.47.00...69.14.17...39.00.17

.00.13.00...00.16.14...00.79.00...00.69.47...39.16.47...00.13.00...00.13.00

.00.67.47...00.79.00...39.69.14...00.39.17...00.13.00...00.00.00...00.79.00

.39.39.00...36.49.17...00.16.14...00.36.14...00.00.00...69.47.00...39.67.14

.00.16.14...00.36.14...00.00.00...00.00.00...00.00.00...36.14.00...36.14.00

CROSSREFS

Cf. A220738.

Sequence in context: A227441 A067820 A263818 * A115612 A281342 A298285

Adjacent sequences:  A220740 A220741 A220742 * A220744 A220745 A220746

KEYWORD

nonn

AUTHOR

R. H. Hardin Dec 18 2012

STATUS

approved

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Last modified June 30 19:43 EDT 2022. Contains 354945 sequences. (Running on oeis4.)