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A212475
Number of 0..3 arrays of length 2*n+3 with sum no more than 3*n in any length 2n subsequence (=50% duty cycle)
1
246, 5211, 93308, 1581686, 26242268, 430682205, 7023308036, 114062278982, 1847205725100, 29854017540652, 481755564098784, 7764949351300178, 125039067197089316, 2011992600375317822, 32354843213417739992
OFFSET
1,1
COMMENTS
Row 4 of A212471
LINKS
EXAMPLE
Some solutions for n=3
..1....2....1....1....3....2....3....2....2....0....0....1....1....1....1....0
..1....0....0....0....1....1....2....1....1....0....1....1....1....0....1....0
..0....0....2....1....0....0....3....1....0....0....2....3....0....0....1....2
..0....0....3....2....2....3....1....0....0....1....1....0....0....2....1....2
..2....1....0....3....0....0....0....3....0....1....1....2....3....0....3....0
..0....0....1....0....2....0....0....1....3....2....0....0....1....0....0....1
..3....2....1....0....0....2....0....1....1....1....0....0....0....1....1....0
..0....0....0....0....1....3....3....2....1....0....2....2....2....2....1....3
..3....3....3....3....1....0....2....1....1....0....3....1....2....2....3....3
CROSSREFS
Sequence in context: A251524 A251517 A293369 * A186787 A229478 A289334
KEYWORD
nonn
AUTHOR
R. H. Hardin May 17 2012
STATUS
approved