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A269438 Number of length-6 0..n arrays with no repeated value greater than the previous repeated value. 1
51, 622, 3674, 14455, 44021, 112476, 252932, 516189, 976135, 1735866, 2934526, 4754867, 7431529, 11260040, 16606536, 23918201, 33734427, 46698694, 63571170, 85242031, 112745501, 147274612, 190196684, 243069525, 307658351, 385953426 (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 + 12*n^4 + (44/3)*n^3 + (23/2)*n^2 + (29/6)*n + 1.

Conjectures from Colin Barker, Jan 22 2019: (Start)

G.f.: x*(51 + 265*x + 391*x^2 + 14*x^3 + 5*x^4 - 7*x^5 + x^6) / (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>7.

(End)

EXAMPLE

Some solutions for n=6:

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

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

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

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

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

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

CROSSREFS

Row 6 of A269435.

Sequence in context: A319542 A173804 A166820 * A269622 A210055 A020278

Adjacent sequences:  A269435 A269436 A269437 * A269439 A269440 A269441

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 26 2016

STATUS

approved

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Last modified May 11 19:29 EDT 2021. Contains 343808 sequences. (Running on oeis4.)