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A200764 Number of 0..n arrays x(0..3) of 4 elements with nondecreasing average value 1
5, 19, 51, 113, 219, 388, 638, 995, 1483, 2133, 2975, 4047, 5383, 7028, 9022, 11415, 14253, 17593, 21485, 25993, 31173, 37094, 43818, 51421, 59969, 69545, 80221, 92085, 105215, 119706, 135640, 153119, 172231, 193083, 215769, 240403, 267083, 295930 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 4 of A200763

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +a(n-2) -3*a(n-3) -a(n-4) +a(n-5) +3*a(n-6) -a(n-7) -2*a(n-8) +a(n-9).

Empirical g.f.: -x*(5+9*x+8*x^2+7*x^3+4*x^4+4*x^5-x^6-2*x^7+x^8) / ( (1+x+x^2)*(1+x)^2*(x-1)^5 ). - R. J. Mathar, Nov 22 2011

EXAMPLE

Some solutions for n=8

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

..4....6....1....4....0....4....3....5....4....3....5....2....4....1....7....1

..3....8....1....3....5....7....4....8....4....7....4....7....4....5....7....6

..3....7....1....5....7....4....7....7....7....6....4....7....4....5....6....3

CROSSREFS

Sequence in context: A328191 A100104 A015650 * A285987 A055365 A209817

Adjacent sequences:  A200761 A200762 A200763 * A200765 A200766 A200767

KEYWORD

nonn

AUTHOR

R. H. Hardin Nov 22 2011

STATUS

approved

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Last modified August 6 14:51 EDT 2020. Contains 336247 sequences. (Running on oeis4.)