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A269496 Number of length-5 0..n arrays with no repeated value differing from the previous repeated value by one. 1
24, 215, 964, 3021, 7616, 16579, 32460, 58649, 99496, 160431, 248084, 370405, 536784, 758171, 1047196, 1418289, 1887800, 2474119, 3197796, 4081661, 5150944, 6433395, 7959404, 9762121, 11877576, 14344799, 17205940, 20506389, 24294896 (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^5 + 5*n^4 + 10*n^3 + 4*n^2 + 3*n + 1.

Conjectures from Colin Barker, Jan 23 2019: (Start)

G.f.: x*(24 + 71*x + 34*x^2 - 18*x^3 + 10*x^4 - x^5) / (1 - x)^6.

a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>6

(End)

EXAMPLE

Some solutions for n=6:

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

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

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

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

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

CROSSREFS

Row 5 of A269494.

Sequence in context: A105946 A050222 A169635 * A221434 A008655 A133754

Adjacent sequences:  A269493 A269494 A269495 * A269497 A269498 A269499

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 28 2016

STATUS

approved

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Last modified September 20 12:05 EDT 2021. Contains 347586 sequences. (Running on oeis4.)