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A250083 Number of length 2+5 0..n arrays with every six consecutive terms having the maximum of some two terms equal to the minimum of the remaining four terms. 1
83, 982, 5604, 21405, 63611, 159278, 352192, 708609, 1323835, 2329646, 3902548, 6272877, 9734739, 14656790, 21493856, 30799393, 43238787, 59603494, 80826020, 107995741, 142375563, 185419422, 238790624, 304381025, 384331051, 481050558 (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) = (7/6)*n^6 + (28/3)*n^5 + (245/12)*n^4 + (47/2)*n^3 + (227/12)*n^2 + (26/3)*n + 1.

Conjectures from Colin Barker, Nov 11 2018: (Start)

G.f.: x*(83 + 401*x + 473*x^2 - 106*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:

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

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

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

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

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

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

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

CROSSREFS

Row 2 of A250081.

Sequence in context: A112766 A128950 A068851 * A292284 A195893 A233332

Adjacent sequences:  A250080 A250081 A250082 * A250084 A250085 A250086

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 11 2014

STATUS

approved

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Last modified December 8 14:38 EST 2019. Contains 329865 sequences. (Running on oeis4.)