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A220742 Number of ways to reciprocally link elements of an 5 X n array either to themselves or to exactly two horizontal, diagonal and antidiagonal neighbors, without consecutive collinear links. 1
1, 16, 258, 5760, 127288, 2792479, 60293428, 1311676964, 28429050419, 616803551956, 13375959455328, 290134376125496, 6292641300928077, 136484527133796904, 2960239399141332140, 64205688074746437957 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Row 5 of A220738.
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)
.00.69.47...69.47.00...00.67.47...00.67.47...00.00.00...69.47.00...00.69.47
.00.36.14...39.16.47...39.36.47...36.34.00...00.00.00...39.16.47...69.34.17
.00.79.00...00.13.00...00.13.00...00.79.00...00.00.00...00.13.00...00.13.00
.39.00.17...69.49.00...00.67.47...36.47.17...00.69.47...00.00.00...00.67.47
.00.13.00...00.16.14...36.34.00...36.34.00...00.36.14...00.00.00...36.34.00
CROSSREFS
Cf. A220738.
Sequence in context: A363689 A041482 A320362 * A266023 A223623 A264532
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 18 2012
STATUS
approved

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Last modified March 29 10:22 EDT 2024. Contains 371268 sequences. (Running on oeis4.)