[go: up one dir, main page]

login
A228284
Number of nX9 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or nw-se diagonally.
2
34, 277, 9637, 186414, 4416695, 97268701, 2197847780, 49208639399, 1105411581741, 24801939723742, 556713719650007, 12494370307905104, 280426447918993931, 6293836975716291709, 141258681814255369288
OFFSET
1,1
COMMENTS
Column 9 of A228285
FORMULA
Satisfies a recurrence of order 89 (see link above) - see Zeilberger links in A228285 for a proof that this is correct, and for a g.f.
EXAMPLE
Some solutions for n=4
..1..0..0..0..0..0..0..0..0....1..0..0..0..0..0..0..0..0
..0..0..0..1..0..0..1..0..0....0..0..0..1..0..0..1..0..0
..0..0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0..0
..0..0..1..0..1..0..1..0..1....0..0..1..0..1..0..0..1..0
CROSSREFS
See A228277-A228285, especially the latter.
Sequence in context: A159776 A295917 A219927 * A248076 A301543 A252999
KEYWORD
nonn
AUTHOR
R. H. Hardin Aug 19 2013
EXTENSIONS
Edited by N. J. A. Sloane, Aug 22 2013
STATUS
approved