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A267469 Number of length-n 0..6 arrays with no following elements larger than the first repeated value. 1
7, 49, 322, 2072, 13216, 83972, 532840, 3381860, 21491464, 136856180, 873803848, 5596638788, 35973158152, 232118471828, 1503949949896, 9786663686756, 63969334316680, 420026972347316, 2770499256109384, 18356852895660164 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 6 of A267471.

LINKS

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

FORMULA

Empirical: a(n) = 34*a(n-1) -490*a(n-2) +3892*a(n-3) -18529*a(n-4) +53746*a(n-5) -91860*a(n-6) +83448*a(n-7) -30240*a(n-8).

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

G.f.: x*(7 - 189*x + 2086*x^2 - 12110*x^3 + 39543*x^4 - 71617*x^5 + 65212*x^6 - 22212*x^7) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)*(1 - 5*x)*(1 - 6*x)^2*(1 - 7*x)).

a(n) = (-504 - 315*2^n - 280*3^n - 315*4^n - 504*5^n + 3409*6^n + 360*7^n + 35*2^(1+n)*3^n*n) / 2520.

(End)

EXAMPLE

Some solutions for n=6:

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

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

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

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

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

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

CROSSREFS

Cf. A267471.

Sequence in context: A200783 A267230 A188868 * A126639 A268942 A269638

Adjacent sequences:  A267466 A267467 A267468 * A267470 A267471 A267472

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 15 2016

STATUS

approved

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Last modified June 12 08:13 EDT 2021. Contains 344943 sequences. (Running on oeis4.)