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A222456
T(n,k) = Number of n X k 0..1 arrays with exactly floor(n X k/2) elements unequal to at least one horizontal, vertical or antidiagonal neighbor, with new values introduced in row major 0..1 order.
8
1, 0, 0, 0, 0, 0, 3, 2, 2, 3, 4, 7, 2, 7, 4, 4, 10, 17, 17, 10, 4, 5, 23, 27, 101, 27, 23, 5, 20, 64, 194, 426, 426, 194, 64, 20, 27, 175, 467, 1722, 1847, 1722, 467, 175, 27, 48, 400, 2375, 8483, 16440, 16440, 8483, 2375, 400, 48, 63, 983, 6320, 46788, 84558, 161779, 84558
OFFSET
1,7
COMMENTS
Table starts
...1....0......0........3..........4............4..............5
...0....0......2........7.........10...........23.............64
...0....2......2.......17.........27..........194............467
...3....7.....17......101........426.........1722...........8483
...4...10.....27......426.......1847........16440..........84558
...4...23....194.....1722......16440.......161779........1752892
...5...64....467.....8483......84558......1752892.......17977932
..20..175...2375....46788.....910358.....18608623......398308251
..27..400...6320...246899....4757427....201223272.....4297235804
..48..983..31706..1263032...51324484...2201719251....98149697258
..63.2498..84949..6568737..271866564..24272631638..1083889273467
.175.6409.426134.34802586.2984245628.268705232398.25078137790680
LINKS
EXAMPLE
Some solutions for n=4, k=4
..0..1..1..1....0..0..1..1....0..0..0..0....0..0..1..0....0..1..1..1
..1..1..1..1....1..1..1..1....0..0..0..0....1..1..1..1....0..0..0..0
..1..1..1..0....0..1..1..1....0..0..0..1....1..1..1..1....0..0..0..0
..1..1..1..1....1..1..1..1....0..1..1..0....1..1..1..1....0..0..0..0
CROSSREFS
Column 1 is A222283.
Sequence in context: A029246 A316995 A338241 * A222673 A222666 A335401
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Feb 20 2013
STATUS
approved