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A221453 Number of 0..n arrays of length n with each element unequal to at least one neighbor, with new values introduced in 0..n order 1
0, 1, 2, 7, 25, 102, 456, 2219, 11640, 65364, 390646, 2472719, 16508791, 115839661, 851634863, 6542134884, 52384882759, 436290809772, 3772143122161, 33797290492507, 313304547351868, 3000631062271288, 29651208549845055 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Diagonal of A221459

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..182

EXAMPLE

Some solutions for n=6

..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0

..1....1....1....1....1....1....1....1....1....1....1....1....1....1....1....1

..0....2....1....0....2....2....1....0....2....2....0....1....0....1....1....1

..2....1....2....1....3....0....2....2....1....3....2....2....1....2....2....0

..2....3....1....1....0....0....2....3....2....2....1....2....2....1....3....0

..3....4....2....2....3....3....1....0....3....0....2....0....0....3....0....1

CROSSREFS

Sequence in context: A221456 A221457 A221458 * A097597 A150512 A150513

Adjacent sequences:  A221450 A221451 A221452 * A221454 A221455 A221456

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 17 2013

STATUS

approved

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Last modified July 24 20:26 EDT 2021. Contains 346273 sequences. (Running on oeis4.)