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A250374 Number of length 1+6 0..n arrays with every seven consecutive terms having the maximum of some three terms equal to the minimum of the remaining four terms. 1
93, 1382, 8964, 37385, 118621, 312578, 720112, 1498569, 2879845, 5190966, 8877188, 14527617, 22903349, 34968130, 51921536, 75234673, 106688397, 148414054, 202936740, 273221081, 362719533, 475423202, 615915184, 789426425, 1001894101 (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) = (7/2)*n^6 + 14*n^5 + (105/4)*n^4 + (161/6)*n^3 + (63/4)*n^2 + (17/3)*n + 1.

Conjectures from Colin Barker, Nov 13 2018: (Start)

G.f.: x*(93 + 731*x + 1243*x^2 + 404*x^3 + 55*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=5:

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

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

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

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

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

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

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

CROSSREFS

Row 1 of A250373.

Sequence in context: A332614 A264556 A250373 * A146125 A017809 A017756

Adjacent sequences:  A250371 A250372 A250373 * A250375 A250376 A250377

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 19 2014

STATUS

approved

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Last modified May 13 01:18 EDT 2021. Contains 343829 sequences. (Running on oeis4.)