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A254704 Number of length 6+4 0..n arrays with every five consecutive terms having the maximum of some two terms equal to the minimum of the remaining three terms. 1
212, 4542, 37204, 183491, 665256, 1961608, 4985336, 11325573, 23567212, 45697586, 83610924, 145721095, 243693152, 393304188, 615444016, 937266185, 1393499844, 2027932966, 2895077444, 4062026571, 5610515416, 7639194608, 10266128040 (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) = (73/35)*n^7 + 19*n^6 + 52*n^5 + 60*n^4 + (377/10)*n^3 + 26*n^2 + (199/14)*n + 1.

Conjectures from Colin Barker, Dec 17 2018: (Start)

G.f.: x*(212 + 2846*x + 6804*x^2 + 1163*x^3 - 472*x^4 - 48*x^5 + 8*x^6 - x^7) / (1 - x)^8.

a(n) = 8*a(n-1) - 28*a(n-2) + 56*a(n-3) - 70*a(n-4) + 56*a(n-5) - 28*a(n-6) + 8*a(n-7) - a(n-8) for n>8.

(End)

EXAMPLE

Some solutions for n=4:

..0....1....0....0....1....1....1....2....1....0....2....2....2....1....2....1

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

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

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

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

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

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

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

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

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

CROSSREFS

Row 6 of A254698.

Sequence in context: A222950 A232671 A082828 * A267062 A250326 A344423

Adjacent sequences:  A254701 A254702 A254703 * A254705 A254706 A254707

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 05 2015

STATUS

approved

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Last modified August 5 17:20 EDT 2021. Contains 346488 sequences. (Running on oeis4.)