A200148 Number of 0..2 arrays x(0..n-1) of n elements with zero n-1st difference.

1, 3, 5, 9, 15, 39, 45, 129, 149, 243, 369, 1365, 2061, 5901, 5951, 7785, 10519, 42519, 59473, 213561, 157559, 278835, 503513, 1553481, 1051639, 2491707, 2981747, 6622209, 10056593, 34139241

Offset

1,2

Comments

Column 2 of A200154

Links

Table of n, a(n) for n=1..30.

Example

Some solutions for n=6
..0....0....1....1....2....2....2....1....2....2....2....0....2....0....1....1
..2....1....0....2....2....0....2....2....1....0....0....0....0....0....0....0
..1....2....0....0....1....1....2....1....0....0....0....0....2....0....0....1
..1....2....0....0....0....1....2....0....0....0....1....0....2....1....1....1
..2....1....0....2....0....0....2....0....1....0....2....0....0....2....2....0
..0....0....1....1....2....2....2....1....2....2....2....0....2....0....1....1

Crossrefs

Sequence in context: A397691 A217350 A210844 * A052007 A117480 A018260

Adjacent sequences: A200145 A200146 A200147 * A200149 A200150 A200151

Keyword

nonn

Author

R. H. Hardin, Nov 13 2011

Status

approved