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A181224 T(n,k)=Number of nXk binary matrices with no three 1's adjacent in a line horizontally, vertically, diagonally or antidiagonally 7
2, 4, 4, 7, 16, 7, 13, 49, 49, 13, 24, 169, 230, 169, 24, 44, 576, 1209, 1209, 576, 44, 81, 1936, 6475, 10732, 6475, 1936, 81, 149, 6561, 34020, 97764, 97764, 34020, 6561, 149, 274, 22201, 179097, 845531, 1495392, 845531, 179097, 22201, 274, 504, 75076 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

...2......4........7.........13............24..............44................81

...4.....16.......49........169...........576............1936..............6561

...7.....49......230.......1209..........6475...........34020............179097

..13....169.....1209......10732.........97764..........845531...........7426986

..24....576.....6475......97764.......1495392........21513936.........316896477

..44...1936....34020.....845531......21513936.......507962194.......12297765846

..81...6561...179097....7426986.....316896477.....12297765846......493466099722

.149..22201...944514...65480503....4672517426....298705742479....19886730240632

.274..75076..4978956..574725752...68571093673...7214603356059...794878208506289

.504.254016.26241679.5050028956.1008146803248.174532135006271.31852650059853831

LINKS

R. H. Hardin, Table of n, a(n) for n=1..241

EXAMPLE

Some avoided solutions for 4X4

..0..1..1..1....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0

..0..0..0..1....1..0..1..0....0..0..0..1....1..1..0..0....0..1..0..0

..0..0..0..0....0..1..0..0....1..1..1..0....0..1..0..0....0..0..0..0

..0..0..0..0....0..0..1..0....0..0..0..0....0..1..0..0....0..1..1..1

CROSSREFS

Column 1 is A000073

Column 2 is A085697

Sequence in context: A207088 A207182 A206994 * A188567 A262274 A223669

Adjacent sequences:  A181221 A181222 A181223 * A181225 A181226 A181227

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Oct 10 2010

STATUS

approved

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Last modified September 29 09:23 EDT 2022. Contains 357088 sequences. (Running on oeis4.)