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A269491 Number of length-n 0..5 arrays with no repeated value differing from the previous repeated value by one. 1
6, 36, 216, 1286, 7616, 44904, 263794, 1545030, 9026500, 52624694, 306261764, 1779708548, 10328981458, 59882754332, 346857774682, 2007544602552, 11611615811212, 67123684593712, 387837889353322, 2239991195959860 (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) = 20*a(n-1) - 145*a(n-2) + 425*a(n-3) - 252*a(n-4) - 605*a(n-5) - 53*a(n-6) + 15*a(n-7).

Empirical g.f.: 2*x*(3 - 42*x + 183*x^2 - 182*x^3 - 286*x^4 - 22*x^5 + 7*x^6) / ((1 - 5*x)*(1 - 15*x + 70*x^2 - 75*x^3 - 123*x^4 - 10*x^5 + 3*x^6)). - Colin Barker, Jan 23 2019

EXAMPLE

Some solutions for n=6:

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

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

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

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

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

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

CROSSREFS

Column 5 of A269494.

Sequence in context: A269580 A269432 A269687 * A269773 A269653 A250358

Adjacent sequences:  A269488 A269489 A269490 * A269492 A269493 A269494

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 28 2016

STATUS

approved

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Last modified November 28 04:31 EST 2021. Contains 349400 sequences. (Running on oeis4.)