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A249850
Number of length 6+4 0..n arrays with no five consecutive terms having the maximum of any two terms equal to the minimum of the remaining three terms.
1
10, 2163, 81816, 1234328, 10653298, 63374127, 289372688, 1084868616, 3492375066, 9959590531, 25736172264, 61283393808, 136218299906, 285494859439, 568743409824, 1083950013296, 1986962835498, 3518666938611, 6042075583672
OFFSET
1,1
COMMENTS
Row 6 of A249844.
LINKS
FORMULA
Empirical: a(n) = n^10 - (19/35)*n^9 + (4327/840)*n^8 - (104/63)*n^7 + (52/15)*n^6 + (367/90)*n^5 - (491/120)*n^4 + (389/126)*n^3 - (221/420)*n^2 + (1/35)*n.
Conjectures from Colin Barker, Aug 18 2017: (Start)
G.f.: x*(10 + 2053*x + 58573*x^2 + 451667*x^3 + 1221975*x^4 + 1285419*x^5 + 529155*x^6 + 77117*x^7 + 2831*x^8) / (1 - x)^11.
a(n) = 11*a(n-1) - 55*a(n-2) + 165*a(n-3) - 330*a(n-4) + 462*a(n-5) - 462*a(n-6) + 330*a(n-7) - 165*a(n-8) + 55*a(n-9) - 11*a(n-10) + a(n-11) for n>11.
(End)
EXAMPLE
Some solutions for n=3
..0....0....1....0....0....1....2....3....3....2....2....2....0....1....3....1
..0....2....3....2....2....3....3....0....2....2....3....0....0....3....1....2
..3....3....0....2....1....3....3....3....3....3....3....3....3....2....2....0
..3....0....3....1....3....0....0....3....1....1....0....3....1....0....0....0
..3....1....0....2....3....3....0....0....0....0....1....0....3....0....0....3
..0....3....3....0....3....1....3....2....0....0....3....2....2....2....1....2
..2....2....1....3....0....3....1....1....3....1....0....0....1....3....2....1
..1....3....2....2....2....0....2....3....3....3....2....3....2....2....2....0
..0....1....2....0....0....3....0....2....2....2....0....3....0....0....0....0
..2....1....0....1....1....3....0....0....1....2....1....3....0....0....0....1
CROSSREFS
Sequence in context: A004821 A328360 A114776 * A334007 A155870 A369811
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 07 2014
STATUS
approved