A250063 Number of length 5+6 0..n arrays with no seven consecutive terms having the maximum of any two terms equal to the minimum of the remaining five terms.

21, 7054, 348066, 6415638, 65419155, 449532868, 2330996068, 9790907652, 34925259201, 109359675810, 307898807590, 793597679082, 1898570817663, 4261710821064, 9053571280840, 18330419662312, 35574363778221

Offset

1,1

Comments

Row 5 of A250059.

Links

R. H. Hardin, Table of n, a(n) for n = 1..41

Formula

Empirical: a(n) = n^11 + (107/420)*n^10 + (9701/1512)*n^9 + (117/28)*n^8 - (919/252)*n^7 + (2677/180)*n^6 - (109/72)*n^5 - (421/63)*n^4 + (6647/756)*n^3 - (535/252)*n^2 - (23/42)*n.

Conjectures from Colin Barker, Aug 22 2017: (Start)

G.f.: x*(21 + 6802*x + 264804*x^2 + 2699790*x^3 + 9862370*x^4 + 14835694*x^5 + 9550828*x^6 + 2483826*x^7 + 209945*x^8 + 2720*x^9) / (1 - x)^12.

a(n) = 12*a(n-1) - 66*a(n-2) + 220*a(n-3) - 495*a(n-4) + 792*a(n-5) - 924*a(n-6) + 792*a(n-7) - 495*a(n-8) + 220*a(n-9) - 66*a(n-10) + 12*a(n-11) - a(n-12) for n>12.

(End)

Example

Some solutions for n=2:
..0....2....0....2....0....2....2....2....1....1....2....0....0....1....0....1
..2....1....1....2....1....1....2....2....0....1....2....2....2....1....2....2
..2....0....1....2....1....2....1....2....2....0....2....2....1....1....1....2
..2....2....2....2....2....1....2....1....2....2....2....2....2....0....2....1
..1....2....2....0....0....0....0....2....2....0....0....2....1....2....0....0
..0....2....0....2....1....2....0....0....0....1....2....2....0....2....2....2
..2....0....2....1....2....0....2....2....1....2....1....0....2....0....2....0
..2....2....0....0....0....1....2....0....2....2....0....1....0....2....0....1
..2....1....1....2....2....1....1....2....0....2....2....2....2....1....2....1
..0....0....2....2....1....2....1....2....2....0....1....0....2....1....1....2
..1....1....1....1....2....1....1....2....2....2....2....1....2....0....2....2

Crossrefs

Sequence in context: A028451 A178327 A231906 * A307931 A270873 A263278

Adjacent sequences: A250060 A250061 A250062 * A250064 A250065 A250066

Keyword

nonn

Author

R. H. Hardin, Nov 11 2014

Status

approved