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A249890
Number of length 7+6 0..n arrays with no seven consecutive terms having the maximum of any three terms equal to the minimum of the remaining four terms.
1
35, 20942, 2027106, 67100334, 1111583581, 11450986236, 83742245992, 473488497480, 2192694269979, 8660886469382, 30052094475746, 93649537009470, 266568651310221, 702331289801020, 1730980486430688, 4025061896008000
OFFSET
1,1
COMMENTS
Row 7 of A249883.
LINKS
FORMULA
Empirical: a(n) = n^13 - (10963/4620)*n^12 + (90131/7700)*n^11 - (265259/15120)*n^10 + (644381/15120)*n^9 - (442943/10080)*n^8 + (322067/6300)*n^7 + (1061/252)*n^6 - (62261/1008)*n^5 + (508283/6048)*n^4 - (1313561/37800)*n^3 - (21229/3080)*n^2 + (8746/1155)*n.
EXAMPLE
Some solutions for n=2
..2....2....2....0....2....0....2....2....2....0....1....1....1....2....2....2
..0....2....2....1....0....2....1....2....1....1....2....2....0....2....2....1
..2....2....1....2....0....2....0....2....2....2....2....2....0....0....2....2
..0....0....0....0....0....2....0....2....2....2....1....2....2....1....1....2
..1....0....0....2....2....2....0....1....2....0....0....0....2....0....0....2
..2....0....2....2....1....1....1....0....0....2....0....0....0....2....0....1
..2....2....0....0....2....1....1....0....0....2....0....0....2....0....0....0
..0....1....2....2....2....0....2....0....2....0....1....2....2....2....2....2
..2....2....1....1....2....2....1....2....0....0....2....2....0....2....2....0
..2....2....2....0....0....2....0....1....1....2....2....1....1....0....1....2
..1....0....2....2....0....2....0....1....2....2....2....2....0....2....2....0
..0....2....1....2....0....2....0....1....2....1....2....0....2....1....2....1
..0....0....2....2....1....0....2....0....2....0....0....2....0....2....1....1
CROSSREFS
Cf. A249883.
Sequence in context: A215570 A271073 A271074 * A285388 A212926 A139473
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 07 2014
STATUS
approved