A269612 Number of length-n 0..n arrays with no repeated value differing from the previous repeated value by other than plus two, zero or minus 1.

2, 9, 64, 612, 7440, 110099, 1923796, 38800210, 887591878, 22714070251, 643030722208, 19954247152834, 673552866591198, 24570545121277999, 963253518328620796, 40387590591059009524, 1803427358679591518028

Offset

1,1

Comments

Diagonal of A269619.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Example

Some solutions for n=6
..5. .1. .4. .0. .0. .5. .0. .1. .2. .0. .0. .1. .2. .6. .1. .6
..0. .3. .6. .0. .3. .1. .6. .0. .1. .2. .2. .2. .0. .2. .3. .4
..6. .5. .1. .4. .6. .1. .6. .6. .4. .5. .5. .2. .1. .0. .4. .2
..1. .2. .0. .1. .1. .1. .2. .0. .4. .1. .6. .4. .6. .1. .3. .3
..6. .2. .1. .5. .3. .6. .3. .4. .4. .0. .2. .0. .0. .0. .2. .4
..1. .5. .1. .6. .0. .1. .2. .2. .6. .6. .1. .5. .6. .4. .2. .4

Crossrefs

Cf. A269619.

Sequence in context: A368291 A113882 A059281 * A269577 A268104 A269683

Adjacent sequences: A269609 A269610 A269611 * A269613 A269614 A269615

Keyword

nonn

Author

R. H. Hardin, Mar 01 2016

Status

approved