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A267229 Number of length-n 0..5 arrays with no following elements greater than or equal to the first repeated value. 1
6, 36, 195, 1030, 5375, 27854, 143695, 738990, 3791775, 19421854, 99344735, 507597950, 2591191375, 13217410254, 67376465775, 343259079310, 1747901098175, 8896431461054, 45262405898815, 230195833919070, 1170328696616175 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A267232.

LINKS

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

FORMULA

Empirical: a(n) = 20*a(n-1) -160*a(n-2) +650*a(n-3) -1399*a(n-4) +1490*a(n-5) -600*a(n-6) for n>7.

Conjectures from Colin Barker, Feb 05 2018: (Start)

G.f.: x*(6 - 84*x + 435*x^2 - 1010*x^3 + 969*x^4 - 172*x^5 - 120*x^6) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)*(1 - 5*x)^2).

a(n) = (-5*(15 + 5*2^(1+n) + 10*3^n + 15*4^n - 97*5^n) + 12*5^n*n) / 300 for n>1.

(End)

EXAMPLE

Some solutions for n=6:

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

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

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

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

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

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

CROSSREFS

Cf. A267232.

Sequence in context: A159721 A106539 A215453 * A048980 A200782 A055299

Adjacent sequences:  A267226 A267227 A267228 * A267230 A267231 A267232

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 12 2016

STATUS

approved

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Last modified May 6 05:18 EDT 2021. Contains 343580 sequences. (Running on oeis4.)