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A212233
Number of 0..2 arrays of length 2*n with sum no more than 2*n in any length 2n subsequence (=50% duty cycle).
1
6, 50, 435, 3834, 34001, 302615, 2699598, 24121674, 215786649, 1932081885, 17311097568, 155188936431, 1391839527240, 12487516404434, 112071578930795, 1006067340461802, 9033468257955009, 81126883587357557, 728697257578499280
OFFSET
1,1
COMMENTS
Row 1 of A212232.
LINKS
EXAMPLE
Some solutions for n=3
..2....1....2....1....0....1....1....0....0....0....1....0....1....1....0....0
..0....0....0....0....2....0....2....2....0....2....1....1....1....0....1....2
..2....2....0....1....1....2....0....0....1....1....0....2....1....1....1....0
..1....1....1....1....0....0....1....2....0....0....1....2....0....0....1....0
..0....0....0....1....2....1....1....1....1....2....1....1....0....1....0....1
..1....0....1....1....0....1....1....0....2....1....0....0....2....2....1....1
CROSSREFS
Cf. A212232.
Sequence in context: A318162 A027330 A090409 * A180910 A199680 A039742
KEYWORD
nonn
AUTHOR
R. H. Hardin May 06 2012
STATUS
approved