A215226 - OEIS

A215226

Number of length-n 0..6 arrays connected end-around, with no sequence of L<n elements immediately followed by itself (periodic "squarefree").

7, 42, 210, 1260, 6720, 40110, 228480, 1338120, 7761600, 45291120, 263674950, 1537291560

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OFFSET

1,1

COMMENTS

Column 6 of A215228.

LINKS

EXAMPLE

Some solutions for n=5:

..6....4....6....0....4....3....0....2....2....4....4....2....0....2....3....0

..3....3....4....2....5....0....1....4....5....3....3....6....4....3....6....3

..6....4....6....1....0....2....4....6....0....5....2....4....5....0....0....1

..4....5....5....5....3....5....5....0....5....0....3....5....6....6....6....4

..1....6....1....2....6....6....3....4....3....5....0....3....3....0....5....6

CROSSREFS

KEYWORD

nonn,more

AUTHOR

R. H. Hardin, Aug 06 2012

STATUS

approved