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A253123
Number of length n+2 0..2 arrays with the sum of medians of adjacent triples multiplied by some arrangement of +-1 equal to zero
1
7, 53, 90, 393, 952, 3323, 9205, 29445, 85717, 264455, 784350, 2382673, 7116997, 21472661, 64312410, 193442021, 579975177, 1742036675, 5224994385, 15683870729, 47048349217, 141182669949, 423540081615, 1270780266933, 3812331343012
OFFSET
1,1
COMMENTS
Column 2 of A253129
LINKS
FORMULA
Empirical: a(n) = 6*a(n-1) -7*a(n-2) -17*a(n-3) +45*a(n-4) -57*a(n-5) +64*a(n-6) +44*a(n-7) -186*a(n-8) +205*a(n-9) -290*a(n-10) +290*a(n-11) -196*a(n-12) +161*a(n-13) -77*a(n-14) +28*a(n-15) -12*a(n-16)
EXAMPLE
Some solutions for n=9
..2....0....2....1....0....0....1....1....0....1....0....2....0....2....1....2
..2....0....0....2....0....1....2....0....2....0....2....2....1....1....0....0
..2....2....2....1....1....2....0....2....2....1....0....1....1....1....1....0
..2....1....2....0....1....2....0....1....2....1....2....0....2....2....0....1
..0....0....1....1....0....1....1....0....0....0....2....0....1....1....2....0
..0....1....0....2....0....1....0....1....2....1....0....0....0....2....1....2
..1....1....1....0....2....1....2....0....2....2....0....0....2....2....1....0
..2....1....1....2....1....1....2....0....0....0....0....2....0....1....0....1
..2....2....1....1....2....0....2....2....0....2....1....1....1....2....0....1
..1....2....1....0....1....2....0....0....0....1....1....1....1....0....1....0
..0....0....1....1....2....2....0....2....1....1....2....1....0....2....2....0
CROSSREFS
Sequence in context: A241487 A236688 A239941 * A352459 A141911 A200766
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 27 2014
STATUS
approved