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A254691 Number of length n+4 0..1 arrays with every five consecutive terms having the maximum of some two terms equal to the minimum of the remaining three terms. 1
22, 34, 54, 86, 136, 212, 334, 532, 852, 1367, 2193, 3522, 5669, 9143, 14763, 23854, 38564, 62381, 100966, 163491, 264822, 429064, 695313, 1126988, 1826949, 2962017, 4802762, 7788052, 12629762, 20482614, 33219658, 53879144, 87389439, 141744960 (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) = 2*a(n-1) - a(n-2) + a(n-3) - a(n-4) + 3*a(n-5) - 3*a(n-6) - 2*a(n-8) + a(n-9) - 3*a(n-10) + a(n-11) + a(n-13) + a(n-15).

Empirical g.f.: x*(22 - 10*x + 8*x^2 - 10*x^3 + 6*x^4 - 60*x^5 - 22*x^6 - 34*x^7 - 6*x^8 - 31*x^9 + 25*x^10 + 15*x^11 + 23*x^12 + 11*x^13 + 16*x^14) / ((1 - x + x^2)*(1 - x^2 - x^3)*(1 - x - x^3 - 2*x^5 + x^8 + x^10)). - Colin Barker, Dec 17 2018

EXAMPLE

Some solutions for n=10:

..0....1....0....0....0....0....1....1....0....0....1....0....1....0....1....0

..0....0....0....1....0....0....0....0....1....0....0....1....0....0....0....0

..1....1....0....0....0....1....0....0....1....0....0....0....0....0....0....1

..0....1....0....0....0....0....0....0....0....1....1....0....1....1....1....1

..0....1....0....0....0....0....0....0....0....0....0....1....0....0....0....0

..0....1....0....0....0....0....0....1....0....0....0....0....0....1....0....0

..0....1....1....0....0....1....0....1....0....0....0....0....1....0....0....0

..0....1....0....0....0....0....0....0....1....0....1....0....0....0....0....1

..0....1....0....1....1....0....1....0....0....0....1....0....0....1....0....0

..0....1....0....0....0....0....0....0....0....0....0....1....0....0....0....1

..0....1....0....0....1....0....0....1....1....0....0....0....0....0....0....0

..1....1....1....1....0....1....1....1....0....0....0....0....1....0....0....0

..1....1....0....0....0....0....0....0....0....1....1....0....1....1....1....1

..0....0....0....1....0....0....1....0....0....1....1....0....0....0....1....0

CROSSREFS

Column 1 of A254698.

Sequence in context: A125526 A181177 A124317 * A159518 A245365 A100039

Adjacent sequences:  A254688 A254689 A254690 * A254692 A254693 A254694

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 05 2015

STATUS

approved

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Last modified August 20 05:25 EDT 2019. Contains 326139 sequences. (Running on oeis4.)