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A249849
Number of length 5+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, 1189, 30080, 337396, 2307418, 11342301, 44075760, 143723664, 409195002, 1045765501, 2447657872, 5325777236, 10897117738, 21155986693, 39251185824, 69997645248, 120555724842, 201316479477, 327036629344, 518272784212
OFFSET
1,1
COMMENTS
Row 5 of A249844.
LINKS
FORMULA
Empirical: a(n) = n^9 + (4/105)*n^8 + (859/210)*n^7 + (161/180)*n^6 + (37/30)*n^5 + (313/90)*n^4 - (7/5)*n^3 + (743/1260)*n^2 + (8/105)*n.
Conjectures from Colin Barker, Aug 18 2017: (Start)
G.f.: x*(10 + 1089*x + 18640*x^2 + 88901*x^3 + 146478*x^4 + 88511*x^5 + 18312*x^6 + 939*x^7) / (1 - x)^10.
a(n) = 10*a(n-1) - 45*a(n-2) + 120*a(n-3) - 210*a(n-4) + 252*a(n-5) - 210*a(n-6) + 120*a(n-7) - 45*a(n-8) + 10*a(n-9) - a(n-10) for n>10.
(End)
EXAMPLE
Some solutions for n=3
..1....1....0....0....1....1....3....3....2....1....3....1....2....3....2....2
..2....2....1....3....3....3....3....3....0....3....3....2....0....1....3....1
..3....3....3....3....3....3....3....2....3....3....2....1....2....3....3....3
..3....3....1....0....0....0....0....1....1....2....0....2....1....3....0....3
..0....1....0....1....2....3....0....0....2....0....1....2....2....0....0....3
..0....3....0....3....3....0....3....3....0....0....2....0....0....3....2....0
..2....1....2....0....3....3....3....0....2....2....2....3....3....2....3....0
..2....2....3....2....0....2....2....3....3....3....2....0....3....1....3....1
..1....2....1....2....1....3....3....3....0....1....0....3....3....3....0....3
CROSSREFS
Sequence in context: A110731 A223119 A233252 * A027879 A194497 A287226
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 07 2014
STATUS
approved