A250018 Number of length 4+5 0..n arrays with no six consecutive terms having the maximum of any three terms equal to the minimum of the remaining three terms

20, 1612, 35440, 375756, 2499284, 12088256, 46481536, 150444840, 425961012, 1083934148, 2528257072, 5485610260, 11197641780, 21695822168, 40183275392, 71552257168, 123070684884, 205276219260, 333121856624, 527422812316

Offset

1,1

Comments

Row 4 of A250014

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = n^9 + (27/70)*n^8 + (146/35)*n^7 + (29/10)*n^6 + (36/5)*n^5 + (29/10)*n^4 - (14/15)*n^3 + (267/70)*n^2 - (151/105)*n

Example

Some solutions for n=3
..2....3....2....0....0....0....2....1....0....3....2....3....0....1....3....2
..0....1....3....0....1....2....1....2....2....2....0....3....1....0....2....0
..2....1....0....2....3....2....2....1....1....1....0....3....2....2....0....1
..3....3....2....1....3....2....1....0....1....0....2....1....0....0....3....0
..1....3....3....2....3....0....2....0....3....0....0....1....2....1....3....2
..0....2....3....2....2....0....0....0....2....2....2....2....0....0....1....2
..3....3....1....1....1....1....2....1....1....0....2....1....3....2....1....0
..1....2....0....0....0....0....0....3....2....3....1....2....0....3....3....0
..3....2....1....3....3....1....3....1....0....3....0....3....3....3....1....2

Crossrefs

Sequence in context: A177610 A130040 A331563 * A177604 A177621 A177628

Adjacent sequences: A250015 A250016 A250017 * A250019 A250020 A250021

Keyword

nonn

Author

R. H. Hardin, Nov 10 2014

Status

approved