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).

6, 50, 435, 3834, 34001, 302615, 2699598, 24121674, 215786649, 1932081885, 17311097568, 155188936431, 1391839527240, 12487516404434, 112071578930795, 1006067340461802, 9033468257955009, 81126883587357557, 728697257578499280

Offset: 1

Author

R. H. Hardin May 06 2012

Keywords

• nonn

Comments

Row 1 of A212232.

Examples

			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
		

Links

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

Crossrefs

Cf. A212232.