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A269622 Number of length-6 0..n arrays with no repeated value differing from the previous repeated value by other than plus two, zero or minus 1. 1
51, 624, 3611, 14125, 43013, 110099, 248143, 507521, 961625, 1712983, 2900099, 4705013, 7361581, 11164475, 16478903, 23751049, 33519233, 46425791, 63229675, 84819773, 112228949, 146648803, 189445151, 242174225, 306599593, 384709799 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = n^6 + 6*n^5 + 9*n^4 + 22*n^3 + 9*n^2 + 9*n - 7 for n>2.

Conjectures from Colin Barker, Jan 25 2019: (Start)

G.f.: x*(51 + 267*x + 314*x^2 + 167*x^3 - 86*x^4 + 17*x^5 - 14*x^6 + 5*x^7 - x^8) / (1 - x)^7.

a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7) for n>9.

(End)

EXAMPLE

Some solutions for n=6:

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

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

..3. .3. .0. .5. .3. .5. .1. .4. .3. .5. .4. .0. .5. .1. .5. .4

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

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

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

CROSSREFS

Row 6 of A269619.

Sequence in context: A173804 A166820 A269438 * A210055 A020278 A160829

Adjacent sequences:  A269619 A269620 A269621 * A269623 A269624 A269625

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 01 2016

STATUS

approved

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Last modified October 18 19:31 EDT 2021. Contains 348069 sequences. (Running on oeis4.)